Downloaded By: [HEAL-Link Consortium] At: 15:59 14 January 2008 @ Printed Phonon Optical Crystals Mol. Institute Chernogolovka, K. Quantitative (Raceiwd and specular of specular symmetry. specular benzene-d6, phenol benzene-d6, intensities and deviation addition from the from For hnn interaction phonon density-of-states Much o-xesv pia spectroscopy optical non-expensive of I Interest opportunity of NTRO Gordon the observed spectra observed the 2) 4) 3) I) the P. the luminescence spectra luminescence this the Cryst. The The There For in MELETOV phonon temperature is time first attention of to spectra PSB D October Holland from ehiu has technique weak non-specularness are most in and Li9. U Solid State Solid the is investigations of phonon of investigations CTl this equal observed. an Breach PSB Cryst.. common the rniin. the transitions. for 142432, unambiguous correlation unambiguous were Transitions side ON 14, the question Side Condon or in shape variation a and has g(o).1-6 1976: observed Science Publishers, different. benzene-do 1977. study osdrd corresponding considered band revealed such revealed Physics characteristic in USSR of non-specularness. been E. of infrnul Vol. approximation initiated, some small of (PSB) was of F. the non-specularness Bands The characteristics of the phononless the 43, given the SHEKA and PSB muiy oeua crystals molecular impurity form the stimulated pp. PSB ais centres radius side shape establishment crystal Academy of /j-methylnaphthalene-d, shape 203-222 Februury recently in PSB spectra PSB bands regularities. Ltd., between on 203 method. The method. turn, in in does were 1977 phonon of h basis the band half width half band (PSB) optical spectra of by of 3. to the Molecular o depend not the Sciences to number a 1977) xlie quantitatively explained the three Specular expression is in PSB the of (SRC) deviation of the of the deviation the of establishment spectrum muiy ytm: benzene-do systems: impurity hs relation this integral intensities integral one-phonon small investigation analysis of are on and the in of of of radious centers to whether presented. the naphthalene-d, shift. USSR. molecular hoeia studies theoretical the by PSB of spectra the crystal of the non-specularness the PSB indicated in of Three the relation the is simple PSB terms possibility observed substracted shape electron- absorption crystals. . phonon Analysis ar of pairs integral of from and the the in in Downloaded By: [HEAL-Link Consortium] At: 15:59 14 January 2008 204 shapes to dedicated experimental crystal^,^.^.^ a has absorption it of simultaneous nonspecularness with crystals wave lengths). wave in to experimental quantitative molecular spectra g(o). which very investigations the escence I defined The on base stability region less function recording. The stability, qualitative il be will Substantial PSB SRC the EXPERIMENTAL a than en studied been validity measurements respect and important precision This hteeti setoee assembled spectrometer photoelectric were hnn density-of-state. phonon and of in spectra in with was have no photoelectric 97 by was shown about absorption some molecular impurity crystals. crystals A and luminescence spectra fact impurity crystals hi relation their % less the precision excited to quantitative a monochromator of netgto of investigation 200 aspect circumstances make correspondence been thorough a investigations 1 and of When successes both integral intensity integral both the of has + o establishing for h cluain has calculations the than 30 of below, have below, watt inelastic pcrm recording spectrum 2.8 was rather phonon PSB studied from this viewpoint.'3-15 this from studied PSB nm of by was left was been K. 97 specially and cm-' Xe absorption and absorption RESULTS attachment checked a in P. asymmetry is % stabilized measurements have of lamp luminescence spectra, decisive width within width well MELETOV to a slow investigation was spectra separation common phenomenon,16 open. was in fundamental based not of PSB investigating with been a used when used in theoretically DMR-4. eto scattering. neutron So, a quantitative a the discovery the PSB series each experiment us been PEP-2. Following in lo00 and on benzene on is continuous in take of AND the civd lately achieved the a and luminescence been and of pure SRC was the crystal carried rule of of of watt The lamp radiation of rsn paper present background absorption (radiation) The a choice E. shape recording the PSB, experiments carried experiments rsa properties. crystal new g(o) the utfe quantitatively justified rather than an than rather and defined the Xe F. absorption by the on spectral width function out and of SHEKA UV view simultaneous fact whether asymmetry whether fact which SRC relation lamp. isotope containing structures (intensity no^.'*^*'-'^ first of the to marked absorption until recently. until spectrum A naphthalene. spectra xeietl materials experimental by the absorption the keep of spectrograph successes in The it optical knowledge The is g(w). PSB has been is the h calculation the quite between and precise sepectrum first eiae t the to dedicated distribution required spectral exception. PSB in of were stability lamp and In some In with consideration spectrum The luminescence the apparatus spectra, H a necessary, result out. of owever, asymmetry number its relation found performed obtaining of PSB radiation Only radiation problem benzene DFS-13 spectra. Lumin- by was g(w) These of cases, over PSB that and was the the the no its or as of of is Downloaded By: [HEAL-Link Consortium] At: 15:59 14 January 2008 and an the carried periments (ph as an (luminescence) transitions and investigations. transitions yia for typical impurity luminescence o the to in symmetrical excited line. in in FIGURE Three impurity Three absorption and Figure the impurity bopin and absorption temperature in by Quanta vibron ground impurity do) electron states, electron the oeua vibron molecular 1 crystal 2 and were selected for is gives instrument AB iga fpclrlcrnc (AC and ofspecularelectronic Diagram (A the phononless (Pd,, shown internal spectra. and luminescence spectra the and The (do or SRC was do the B) short systems, namely, the benzene-d6 systems, the crystal namely, CD ahhln-, crystal naphthalene-d, in out. respectively. in investigated systems spectra investigated and in in 42°K. regimes uiecne respectively. luminescence, d6), A spectra. optical correspond phonon d,) d6. Figure sensitivity. excited In simplified wave lines the The SIDE PHONON ae en selected been have all comparison transition benzene-do crystal with of (C (absorption) 1. the (PL) impurity of e2,. absorption and absorption and to small schematic representation The the xeiet,uls otherwise unless experiments, D1 followed The internal electron radius The errors from A,, concentrations BANDS absorption with CAIand vibronic(AD and sides local centres. System most + phonon states wide by did B,, for -ehlahhln-, as P-methylnaphthalene-d,, luminescence spectra and were PSB nesv pclr vibron specular intensive not is The regions performing x represented frequency had phenol e29 pcrm consists spectrum exceed the from pcr correspond spectra were the of with series ih benzene-do with of of absorption in the as 8% by form the external 10% h ground the quantitative an impurity an CB) a non-totally of long thick broken thick molecular in the in specified, which transitions and electron phonons of wave and 1 the ex- 205 and % of is Downloaded By: [HEAL-Link Consortium] At: 15:59 14 January 2008 206 difference absorption creation. The creation. the frequencies and C. areas Total crystal. FIGURE of the of the long with ~~~ Luminescence. e As BL/,~ d,, h in ph 120 Crystal narrow short The respect PSB in wave seen in d, do narrow 100 highest Spectra 2 d8 integral intensity normalized are wave are to from PSB. in PL and it. 60 represented Absorpt. Absorpt. Lumin. Absorpt. Lumin. Lumin. peak pcr PSB Spectra the luminescence PL PSB with the The of luminescence 6D of ground Quantitative characteristics intensity PL with Figure the distance corresponding K. w,,, and 40 vibronic specular P. om,, 0.66 0.43 0.38 0.66 0.20 0.43 PSB in is (606 = Integral MELETOV 2, 20 taken Table spectrum intens. _+ k 38371 k k a between = are cm- 0.05 0.02 0.04 0.04 0.05 0.02 marked difference marked spectra. 37245 0 normalized for TABLE I. cm- ’) to unity. They include They 20 AND transitions and 0.88 0.38 1.00 PLs 1.00 1.00 1.00 the m’ and cm-’ a a has 1 ’ Quantitative Relative peak Relative of The I intensities” Peak positions. Peak intensities” and 40 excited E. transitions per per is phonon 0.62 0.42 0.33 0.27 1.00 1.00 equal intensity F. 23 similar unity half AD 60 unity in each spectrum. in each unity SHEKA is side (520 and 0.18 0.16 0.19 0.42 the width in to the - - 80 observed = of both structure and structure bands CB with hrceitc o the of characteristics different cm- other 2.5 KIO of r sum spectra. cm-’ the impurity the *I externai phonon externai 46 44 45 ’) 37 32 36 = peaks 120 states. The in of 2.5 0- integral 95 92 73 78 74 58 PSBs u. 2 e2@ are and cm- Absorption. w, consists phonon measured 100 132 127 - - cm- do 79 3 of of cm’ PSB and in the the PL I d, Downloaded By: [HEAL-Link Consortium] At: 15:59 14 January 2008 e. crystal. intensities, FIGURE ratio peaks with respect with peaks in symmetric developed rum. crystal 36079 of 35065 of absorption h long the integral intensities (with respect spectra PL Due tive Luminescence. Figure Figure luminescence absorption are characteristics for The to Total cm-' cm-' ph of the small the 3 not three main 4 luminescence spectrum consists also 3 wave the impurity in the different shows Spectra vibration areas structure gives affected and and do. e and and of PSB. and The the r of concentration the r luminescence spectra PL luminescence recording. to the vibronic the of = PSB = pure (phonon absorption, by and phenol impurity concentrations impurity phenol corresponds absorption the The the 2.5 2.5 crystal intensity distribution peaks ebopin and reabsorption PSB PL electron transitions cm-' observed cm-' PHONON structure positions. are specular frequency /Id,, 1 to followed the integral the intensities normalized (phonon and respectively. : the unity) o h vibron the to 1, in difference. SIDE of transitions : d8 luminescence 1 is 3, h both the with 480 1 by BANDS absent. frequency the per However, are are the which cm- of impurity unity different of AD The narrow The absorption and equal. The equal. the same within short the narrow Table and l) PSB transition in is in the in spectra oh spectra. both 534 CB seen the were wave a positions concentration of I is of shows cm-') specular symmetry specular resonance electron from the intensity similar. absorption the 0.2 narrow PL PL PSB of with impurity % luminescence the with the quantita- with the u. followed of with and Absorption. a, The the accuracy impurity PL w,,, w,,, ph 0.01 totally 0.65 a spect- three PSB with in well 207 by x. do = = "/, Downloaded By: [HEAL-Link Consortium] At: 15:59 14 January 2008 208 partially e. FIGURE PSB in w,,, difference this corresponds to ture. The frequencies maximum Maximum Curves spectra them are close spectra. tively position the For above PL we Luminescence. ds Figure have crystal. maximum from transition PSB structure all Curves = to in deuterated 70°K. in 4 31171 within The the the specularly the shifts 5 failed different relative going Total is Figure 5(a) Figure PSB. Spectra position shows positions and like systems measurements in At Parts in areas 6(T) cm-' shift the is Figure the to molecules When the absorption and from. that these curves of represented integral intensities coincide intensities integral within measure of purely of and the experimental for intensity values K. the spectra the of investigated, PL in and are the 5(b,c) temperatures, symmetric electronic eemnn the determining P. the three half the main the and impurity the of plotted according plotted the electronic MELETOV r the luminescence showed are PSB the two width are = experimental of by PL obtained specular 3 are are h same the luminescence halfwidth the above plotted according plotted impurity crystals impurity the error cm-' one broadenings peaks normalized shown the spectrum the and that the transition PSB AND it arw resonance narrow as after separating after transitions cases, followed is of by halfwidth followed and possible. spectrum low-frequency for impossible E. and broken lines. broken error about PL to per F. intensity i.e., absorption and absorption spectra in in luminescence y( unity temperature shift SHEKA AC absorption. by though T) both obtained the maxima the 0.4 by with increasing with y(T) to the and and in the to values both is cm- to luminescence h short the spectra ad associated bands distribution h absorption the CA long practically of and the part substract PL spectra. the I. of proved at broadening and tendency and absorption and wave In luminescence, Unfortunately, impurity the the with increases PL shift luminescence (see temperatures a. wave shift maximum Absorption. PSB. the the tempera- correctly Table to to between spectra. ih the with of lower same. be same &T), rela- PSB one. The fld, the 1). as Downloaded By: [HEAL-Link Consortium] At: 15:59 14 January 2008 C) crystal broadening FIGURE inhomogeneous broadening inhomogeneous relative regularities when The from PLs respectively, varying with from a frequencies integral intensities integral PSB do luminescence spectrum The Consideration 2) 1) in were shift 0 The The qhape. specular symmetry of the of symmetry specular d,. the =a to h in ph PL 5 8 values I- approximated most L non-specularness temperature PL shift cm- values and do This temperature broadening common the Ah to are of and are non-specularness are is the PSB of the different. 3 also from PSB equal cm- oe nry side energy lower three above pairs above three low-frequency varies by characteristic feature to temperature different. PHONON y(T) Y in 0 the of ' an was to or and SRC For the = from Lorents absorption 4 different. PSB 2[r(T) practically cm- (7) for PSB the absorption and The SIDE and reveals 4.2"K shape, the crystal crystal part over - It shape does not depend whether depend shape does not for curves. shift value r(4.2"K)I. BANDS is of the first, second and one. intensity increasing of the same to temperature-independent.8 that observed for observed as / spectra leads spectra maxima y(T) of d,, We 50°K. the PSB bdl0 in is, varies from luminescence also d, J non-specularness maxima (6). / spectra range. in The Ad a) believed d8 ,!ldlo is all PL Ah to the to 7 is shift three in 0 cm-', is in the third temperature to d,: that the that spectra. about going from u 6.5 following deviation b) to crystals. crystal, ph for cm- of lower in zero PSB 209 PL the the do; ', Downloaded By: [HEAL-Link Consortium] At: 15:59 14 January 2008 shift. The of PSB 210 addition equality, spectra show observed for the theoretical follows A theoretical first shows crystal phonons electron 2 Thus, are interactions, Herzberg-Teller spectra Index tion 4) In 3) The It specular Using universally lot SRC. found rn-odn part Frank-Condon BASIC is part P(o) non-specularness For There ht follows what that the luminescence the of well g up as up analysis force under matrix can be can classified description, we will to wave can papers refers that in weak to larger and known rcial ay pclr pair specular any practically and shall symmetry conclusions the is REGULARITIES be terms the take h phonon the be is an of function PSB experimental results. experimental different of to transition, the disturbance the transition, divided nucleus equilibrium position shifts position equilibrium nucleus (less) are part use the emission on nmiuu agreement unambiguous the a change a that the that of the of respectively. we accepted terms, shape K. devoted mainly the mainly non-specularness of the of non-specularness the (HT-interaction), in available temperature and P. and as hl consider shall in into two parts into two the are on (FC-interaction). value P'fw) oen theory modern MELETOV SRC one of interaction of interaction SRC spectrum non-specularness. P'(w) the P"(0) the in PSB absorption the in to OF ground and ground the centre the temperature variation temperature a photoexcitation. data a = nucleus investigation^'*^*^^-^^ different aspects of the shape. = or ovnet om o te oprsn of comparison the for form convenient ELECTRON-PHONON const. variations, photon - const. let us let e AND three pairs listed three above. and and 0 for in is spectra characteristics spectra the w. phonon coordinates. of due results the h eeto-hnn interaction electron-phonon the the absorption the express the probability E. T"(4 of As excited by Ze(m). of PSB between oeua crystal molecular F. lcrnpoo interactions electron-phonon adiabatic optical to is SRC PSB the the SHEKA known, the The of hamiltonian xeietl regularities experimental of states larger our PSB integral, dependence and electrons second part, second h problem. the h expression the of As approximation. The approximation. where other the in as nerl intensities integral PL (less) and a the general INTERACTION a FC-interaction half result is change investigations luminescence with the are and disturbances SRC observed of of width called different. principal the is external In of absorp- optical called of in what SRC case. both and the the the (21 in Downloaded By: [HEAL-Link Consortium] At: 15:59 14 January 2008 P(o) For coupling termines function where kernel Condon In a {a) the EPI-kernel the However, on where rather a rather and Here where t the K the Condon ecie the describes It describes is expressed and is &(K) of absence electron-phonon meant simple expression approximation. contains the of the K', it can SRC approximation is .M(K) EP-interaction (EPI-kernel). EP-interaction both PL. PSB the of is be electron- at electron rather information The the HT-interaction, the function the HT-interaction, the and shift Fourier simplified in shape eotmeaue as temperature" zero f9(w, function M(K') of (EP) cumbersome and cumbersome and PHONON for in 7,) state qiiru pstos te function the positions, equilibrium component irnpoo interaction. vibron-phonon are interactions? absorption = P(O)'~ on the on rPo(0,T) with some nonzero SIDE lattice vibrations. lattice crystal cases. of BANDS As + and only complicated the electron transition moment, transition electron the in shown One hnn spectrum phonon the luminescence for general form, of T). ftK.(t) K in the = l2 in tc' cases It the does not depend not does the = can expression 0. pcr. This spectra. general case. general is the function be So and ftK.(t) due to called one on has the the de- for 21 (4) a 1 Downloaded By: [HEAL-Link Consortium] At: 15:59 14 January 2008 depend 212 and ally luminescence termine known. determine repeatedly of phonon by one-phonon impurity be one-phonon multiphonon the change. terms probability and accuracy the Here it where rium Equation The According is Formulae kernel calculated a m-quantum vibronic intensity m-quantum solved at phonon describes the known linear term linear position under photoexcitation. In the In photoexcitation. under position t4 fo(o) with possibility on the mode. is h function The On crystals. of determination index the dimensionless the investigated’.’.’ the does that EPI-kernel respect these corrections. (5) frequencies change (4c) h ohr hand, other the transition transition to T processes by spectra Functionsf, is kernel = (4c) is multiphononness not g, perturbation in and of PSB the shape. In of expressed 0’3’,’8 f so to the depend g(w) and solving Eq. ra practical great K. that are (4d) W. $d(w) by by P. probability probability. in EP-interaction is, in is, (a), = + equal. when an PL MELETOV The PSB. the make ’ I,,, fo(4 on ~~adco’fg(co’. andf2 as and experimental shift PSB some is and theory. = the W analyzing function Cpg(o, (5) in From the exp( its + it and is is PSB of is the nes polm can problem inverse is are the corrections caused corrections the are cases, flh) if importance determined” solution results solution possible due Condon approximation,fg(T) Condon The AND rn-phonon completely defined atom fl(o)andf2(w) -y2) T) also At the hamiltonian, the integral intensities integral hamilt~nian.~ fo(w) mainly zero function. PSB luminescence spectra enl coincides kernel T)o’+g(o + the procedure the FC-interaction important E. analysis PSB. - (Y2)” equilibrium positions equilibrium m! free fdd F. to temperature is SHEKA . This to rcs probability process estimate because h one-phonon the molecule vibron spectrum, by + the shift the The of - are is in . . equation because the procedure because the If the w’, small, the . linear and 3 term problem if of constant it a be FC-intera~tion,’~ T) in is expression’ the EPI the exactly allows of determining the contribution 1 absorption described the formulated . atom W, was by kernel describing in frequency transition quadratic y2 has us numeric- with does kernel equilib- of the to to de- to some been only and can qth not the the (6) (5) of to is Downloaded By: [HEAL-Link Consortium] At: 15:59 14 January 2008 (4b) In transition which possibility tion deals in excitation described excitation bv cnieain the consideration, above tonian phonon of-state caused the nonspecularness and nonspecularness the g(o) find other. The problem In attention In might circumstances cated. ness form been interrelation aitna terms hamiltonian constants Here Thus, An The the absorption Going turn, addition, one has one addition, can as out and is, first obtained attention with 1; PSB is be second circumstance causes by it is g(w) if function be it how much how in frequency change quantitatively. a non-monotonic back has to follows from the expression follows the from the one-phonon the providing is of the PSB the perfect primarly problem of the correspondence. seen the Condon of expansion the and recently' been make the all, should to available possibility available EPI-kernels f,(w. PSB quantitative PSB nonspecularness. from the luminescence spectra. h PSB the analogy is are the hw in5. shown shape justified the for' by to closely question on the adequacy the on question approximation T). processes be proportional kernel (7) the take problem coefficient, V constant with paid h more the PHONON non-specularness. and that function to hne n hnn rqece under frequencies phonon in change quadratic shape is connected into by the The in expression and the associated to W not So, checking the Is absorption approximation of two following two yz account that the that account measuring question connected non-specularness, The analysis. the of the 9; the SIDE is substituted is different to to is frequency in term one-phonon function one-phonon is with kernel PSB each more term met connect integral intensity integral the normal coordinate, the normal The (8). with BANDS on the PSB W expressions and The and As other in connection, concerned PSB with h EPI-kernel the the PSB the as in the similarity the energy units. circumstances. that of one the g(w) a h Pitrcin Hamil- EP-interaction the validity uiecneseta has spectra luminescence integral intensity equality g(o). by the whole PSB W, and weighted shape observed non-specular- the can conclude can f similarity we the more pronounced more the general g(T) and So are and the and linear (4) would of but non-specularness. of the to phonon density- phonon from expression expressed differ each from the of atr in factor The the (9) only case. and quadratic next and The the very approxima- EPI-kernel. like o( present m-phonon relation and part from PSB step h one- the All first with compli- photo- to in these p is of and one pay the 213 the the the are (7) to at it Downloaded By: [HEAL-Link Consortium] At: 15:59 14 January 2008 214 change T Here listed EP-interaction listed if Expressions obtained serve molecule expect can equality can be can As total spectra. b integral into interaction could interaction PSB pendence transition is 1 where The relative the . linear. In this = For lo-’ it Herzberg-Teller be 0 function account. has first one is B’ shape phototransition as weak is expressed as1* is analyzed from that inphonon considered = intensity has The value owing been of by proof on dipole moment dipole irn spectra, vibron P/a2 transitions, the transitions, HT-effect can Eq. pia transitions optical (1 the nonspecularness. disturbance k &,(o, The 1) noted earlier,15 noted of to and and known of case, (5). and PSB the HT- and HT- the frequencies e neglected be its first the with Then T) k’ K. (12) make the been model. originlg effect the nerl intensities integral intensity 4Bm(OlT) in is connection as P. consequence good accuracy in accuracy good intensity of described its positions discussed above. expression a M(R) MELETOV shown” solution is intensity equality comparison with comparison in and the The and restricted it Citrcin. in lsad minus and Signs plus FC-interactions. PSB with and = on is possible distribution as HT-effect in (1 low can the latter of by for the case of the a AND oscillator k (3). of check h osre non-specularness observed the Eq. expression external for be ms)24$(OIT). this dependence The be in to follows from follows of E. the (5). observed only observed some substantial calculate on fet is effect antd approximately magnitude F. absorption the is influence The in Condon PSB, strength, the when phonon SHEKA accompanied PSB calculated one esn. hs oe could one Thus, reasons. (4d) second kernel can also correctness as of the the one has and in the case approximation, and of the the normal coordinates normal disturbance exceeding W and the kernel in the q electron should term P-enl de- EPI-kernel systems whose systems determines the form by luminescence HT-effect of by by that the in of (1 be another 5 the the photo- above- 1) of . of taken lo-’ refer with may EP- and free the the on by be Downloaded By: [HEAL-Link Consortium] At: 15:59 14 January 2008 difference to Ref. and function additional described between the particular. of As 3 and relate analysis in investigated systems show systems investigated define Condon approximation. Condon general case general to system. kernels stitutes experimental according 0.088, and contributions Even absorption and absorption The The PSB The Figure be the follows from qualitative Use luminescence 12 are carrying equal to respectively. EPI-kernels Condon results integral is PSBs from simplified from expression the are These 0.316 shown of of 42(w, the the the 6 in above, to only shows theory factor determined values to the comparison and the general case general xeietl PSB experimental corresponding out and errors. of of 1.15 bands analysis T). as contribution the one approximation. PSB intensity. PSB expression vanishes. Therefore, processes the the PSB luminescence spectra 2 spectra (1 Because the '1 agrees J'"(w) results and It previous section, the initial stage and of within & were used were two is nerl neste oprsn carried comparison intensities integral The of subsequent these correctly. of seen from seen 1.2 2' #!(4 of absorption and well the crystal the other impurity systems can impurity other in of PHONON curves PL for for of the that with ae sbtnily opiae te relation the complicated substantially makes 0.2-0.3 spectra to order of the f'(w). this, a = relative integral with experimental nest determined intensity h n-hnn transition one-phonon the processes with processes as Just h iprt crystal impurity the and which m EP-interaction expi in Figure (13), the quantitative functions to = The may SIDE Figure the experimental the and may e, phonon state phonon for ascertain whether ascertain the 2 -f9(0))f9(4 possibility it respectively. respectively. has and values luminescence spectra give is hs esn the reason, this prove 6 BANDS possibility seen 6. that the rn @(w) data rise fg(0) PSB rn = to the that analysis or form of = 3 be to density and analysis they may they intensities The finding PSB are equal are As of I = the of erroneous. a do by value in be of quantitative I?'% it more using @(w)t the introduction difference in principal has PSB of exp{ #g(w, considered PSB also the dwfg(w) proved d, were spectra studied spectra 0.33. PSB, been shown than of PSB be in out -fg(0)} to is refers in quantitative EPI-kernels vanishes, T) the absorption 0.367. dealt calculated 0.220 Thus, the Thus, Eq. for like structure two-fold is even and analysis ph within to in of (5) three in with con- that The (14) and the the the the for 215 do in to in Downloaded By: [HEAL-Link Consortium] At: 15:59 14 January 2008 fe(w) 216 spectra between FIGURE tions 40-50 for curves is quencies effect investigation and according to asymmetry discrepancy frequency from For area under tained."-' rvd to proved due Figure /? a relative intensity relative ne the under to O.OOO1 with of obtained = more detailed analysis detailed more to cm-' e the (1 in Figure in one-phonon 6 the linear one according and -0.0:4. one-phonon under impurity molecule photoexcitation molecule impurity under 7 change since curve PSBs m be like gives 2) is to Eq. and of = and w tms larger times two (1 u to due curvef"(o) rm PSB from 0.01. the 2 that (1 Unfortunately, the parameter Unfortunately, and 6). 1. are (I' the (2 and I) On kernels using kernels and and It K. 1') was of The described distribution processes results of the is m 2') approximations P. 2') calculation, PSB the specular also performed = and curves. respectively. curves. best MELETOV parameter as numbered 3 multiphonon of which of seen become significant become a agreement the in by to the result hn the than relation calculated both spectra. both The vibronic (1 weakly that effect, indicates thef"(w) for kernelf"(w) AND 1). 2 reflects It of a (3 the functions the in in transitions set should we and (1 a. E. between solving changing functions changing expected which Figure 1). Absorption. of for F. have 3') that nerl intensity integral only value parameters transitions, obtained transitions, SHEKA the be calculation only of carried expression a Eq. the ratio 7 the noted, is the twof"(o) contributions change in change makes n. Presumably, one. is 4!(w) essential e. ph in ph (5). in position made equal made Luminescence. out the however, p' do The no of have the have over crystal, calculated by an additional an was region (I the (see comment phonon in for as calculation 1 of h kernel the ) quadratic the a this of obtained was 3 maxima difference that curve to transi- and above range shape case. that this ob- fre- the on 3' 2 Downloaded By: [HEAL-Link Consortium] At: 15:59 14 January 2008 crystal principal mum and u. crystal This the neutron for side. PSB to small FIGURE bance of the impurity electrons the is impurity system impurity values E. by Research Absorption. t Figure Figure rather F. muitiphonon E. 5°K the structural The and The Sheka at Sheka fact L. values of of at phonon NIIS Bokhenkov, acltd by calculated shifts low-frequency maxima low-frequency shifts (JINR) 7 difference 80°K opeey described completely is the the low-frequency maximum low-frequency appears 9 8 e EPI-kernelsJg(w) located e. incoherent pcrm was spectrum ersns the represents compares the of PSB crystal Luminescence. at and density-of-states intrinsic Laboratory Dubna. pdlo processes data V. to integral in 5"Kt between (1 G. phonon 1) indicate the in interact mainly interact EPI-kernelj'(w) at inelastic the Fedotov. obtained d8. growth it density-of-state. (1 of T follows intensity. PHONON is kernel the and From results Neutron = spectrum 0.09), that J. 138"K.'l from polycrystalline benzene-do at benzene-do polycrystalline from maxima by scattering 1') region g(~).'~ Majer, that calculated the f'(o) the f'(o) one-phonon which of Physics SIDE (2) picture by with. a decrease impurity the ofg(o). 1. well g(w) when From From Natkaniec, does not does and 5 It (NIIS) BANDS is (LNP) by similar + is showed and employingfe(w) in (5) it 7 The functiong(o)is h calculated the just the disturbed states disturbed the just the picture the the good is cm-' processes molecule causes molecule when of off"(w) spectrum in seen M. coincide h Jit nttt for Institute Joint the comparison PSB temperature up employing unkKrniwth and Sudnik-Khrynkiewitch gemn with agreement to that in is rcsig for processing the it (1'). (the contribution (the further from the in with T is ihr energy higher Crystal benzene = the this case this CL region seen of the from 80°K g(o) the distur- the experimental calculated increased. g(o) benzene that h in ph and Nuclear 138°K of maxi- small with PSB -do that 5°K the the the 217 do. Downloaded By: [HEAL-Link Consortium] At: 15:59 14 January 2008 phonon FIGURE 218 calculated difference ih h crystal the with agreement FIGURE diffraction attained calculated ee the were Kitaygorodski obtained are obtained The density-of-state PSB 9 8 between spectra for 0 0 combination Calculated PSB by on of shape p’ rcial qa.I Figure In equal. practically the the of the crystal the (1 = (1 parameters. one-phonon and d8 and -0.OOO1 kernels Pawley non-specularness g(w) by 2) K. phonon 40 40 1’) and (5) of P. of of the benzene-do crystal’ the EPI-kernelj”(w) f”(o) (1’ at h specular the MELETOV (2 methodz2 (see h unit the and and h structure The T density-of-state Figure = band on obtained 2’) 2’) 80 80 4.7”K, and multiphonon curves, respectively. cell AND is very is electronic transitions electronic using 10). of and parameters, the E. Thus, kernelsf‘(o) the 11, atom-atom data, I20 I20 weakly ph the (2). F. the atom the g(o). the in SHEKA (3 basis do used and a. kernel The crystal Absorption. pronounced. The pronounced. 3’) obtained of of in positions fitting positions transitions, potentials 160 160 f‘(w) function the Eq. (1) I the &f,, and the calculated the and W, W, (5) e. calculations, is Luminescence. by Ccm’ and in obtained as compared andf“(w) g(w) with ds neutron (1 crystal, good 1) was the the is a Downloaded By: [HEAL-Link Consortium] At: 15:59 14 January 2008 e. FIGURE and FIGURE phonon case, is potential terms contrast, there spectrum Bokhenkov, Luminescence. brought into accord brought As t calculated The thef'(o) to of density-of-state e 10 NIIS I the impurity the theoretical ideas presented ideas theoretical I minimum from I. by EPI-kernelsf"(o) Calculated Natkaniec, pcrm rm the from spectrum ( 1 the maxima is 1) EPI-kernelf"(@) likely polycrystalline sample g(w) in by V. the crystal with G. of (5) an do the naphthalene-d, the Zhebelev, best (I EPI-kernelj"(w) PHONON inverse not the and polycrystalline do way.23 (2) positions coincide 1') in employingf'(o) calculated and tendency. d, SIDE in E. The (Figure section F. Sheka of with d8 of crystal BANDS the position dR by corresponding peaks corresponding at Bdlo (5) was the (1'). T 2 2), at (2). when leads = in obtained LNP Crystal region the of d, 80"K.t employing experimental PSB employing experimental crystal low-frequency ofJINR analysis to Pd, the conclusion of at As (1) high T in at and in ds. = Dubna. of L 80°K the a. in density. the calculated its Absorption. the previous maxima by PSB NIIS E. that 219 By in L. Downloaded By: [HEAL-Link Consortium] At: 15:59 14 January 2008 effect. the phonon present, 220 estimated. and above noted CONCLUSION In corrections tofo(w) corrections density-of-state. one-phonon As one can theless, equality having optical perimental are function under fact that g(w) andf,(o). with crystal. with impurity possible we have we from crystal impossible having As When analyzing this centre this analyzing When conclusion seen difference the do be ant obtain cannot is those isotopic impurity, as impurity, isotopic Figure seen that the excitation. The to more in it the maximum isotope sought in rniin can transitions The different relation different PSB from expression from the fo(o) frequency g(o)) to the singularities the the met with met is SRC d6 this These As from ey effect very difficult of the host crystal host the of h analysis the pcrm can spectrum associate only crystal^'^-'^ value 2, valid for valid analysis shape. transitions even is procedure case, in we = or between PSB clear from section clear the corrections The It the fe(o) SRC group SRC shall formulate the formulate shall of the is in hneudr excitation under change too, to .f'?,(o) of From above-listed example, above-listed eed on depend impossible K. PSB the of the rbe of problem the the obtain a may specular spectra are affected following in be which not the not P. the the crystal used case of (7) fo(w) the correspondent crystal. the correspondent of change cannot change impurity is singularities to integral intensities must integral MELETOV described from be this also it PSB PSB incorrect. the are only the function describing the probability of probability the describing function the only h crystal the free shift of by raised is has g(o). pure group functionfo(o) but viewpoint, now the is functionf'(o) give rise give fg(w). the the us met difficulties. In structure at of defining A, been associated 2, system PSB earlier for Condon approximation SRC less So, this defect may value to tbe in AND only (do we with conditions in calculate these corrections. Therefore, of One the there the closer the under shown in level benzene may absorption phonon to be functions Pd,, of then a comparison a E. and the and an d,) the the Condon a change a a only can estimated. n the on F. the the is not accuracy offg(o). yields are such conditions. with second remark second the function in when above SHEKA a under PSB a phonon and spectrum grave apply d, far from far to sum phonon by benzene crystal, pure crystal, benzene be be @(w) spectrum. approximation. PSB PL the the specular the than analysis in the the naphthalene use the only l3-I5 of which Hence, In of doubt split the fo(w) the betweenf'(cu) weighted functions shape with frequency HT-effect for pairs system h approximate the corrections h naphthalene the being for density-of-state. due procedure is PSB off and ph an of The from is defined. any impurity whether those the effect the It by of to can benzene-do in due to due agreement associated symmetry of should shape. it impurity 49 the specular [see do. crystals, phonon making isotope the change is Never- not of cm- fi(w) used seen HT- (6)], The and it the the ex- At be be or of is Downloaded By: [HEAL-Link Consortium] At: 15:59 14 January 2008 cm-’. from becomes isolate totally symmetric totally spectra be one-particle the details essentially of when pecularities solution the substantially discussions The authors Acknowledgements Mr.’A. M. Tsyganok Mr.’A. References 16. 14. 17. 15. 13. 11. 10. 12. 2. 4. 6. 9. 5. 3. 1. 7. 8. In All dissociated Observed fiz.. ( K. R. R. V. V. G. R. P. R. L. V. rela. M. D. I. I. Rw.. 1. I. g(o) I971 S. pure S. S. S. h beginning the A. S. I. calculating L. said K. M. Kopelrnan, Kopelman. P. L. E. F. A. 37. PSB. In Osddko, Osadko, Osadko, Personov. is 18. Osadko and Osadko ). Kukushkin. Broude. Reynolds, 133, Meletov McCumber Dolganov. Broude. Imbusch. of Hochstrasser Krivoglaz, akd only marked structure of the 31 aggravated consider 766 (1976). above shows of over-lapped.26 the naphthalene the I A of Experience shows Experience PL only its (1973). limited, 1029 results. E. the Fi;. Fiz. vibron V. vibron problem and F. F. V. structure 1. W. (so-called Chem. 1. K. it the K. S. for (1964). W. W. Fiz. Fiz. and for ircrdoqo S. fivrdoyo vibrations. In K. phonon Alshitz. E. to remains Osddko. M. Dolganov. and P. A. his Mrs. of Ochs, Ochs. Dolganov. be F. two-particle /wrdo,qo irerdoyo by M. and one-particle vibron one-particle excitation Meletov. Phys. Yen. absorption Zhdanov. in their pleasant P. Sheka. help intrinsic that crystal is D. the N. have remained questionable, and Though /elf/. rela. N. the and P. and and still rather PHONON density-of-state E. A. Sturge, 1. in Lett., M-band) Prasad. the the possibilities dissociated F. /do. ids. Shikina R. D. fhj.s. P. preparing 15. 17. L. region and F. the B. that Godydyev. 1. Ix. N. N. the absorption the Schdwlov. 22. 2892 2429 NUS 5. this 8. 6. absorption, with Slobodskoj. and Personov. compli~ated.~~ J. E. the absorption Prasad. Prasad. S/ar. duty only 2170 J. 1707 Slobodskoj, and Slobodskoj, AN region 177 and Appl. F. practically SIDE (1975). (1973). Chem. of case, n two-particle and isolation the English version English the Sheka, external pcr though spectra (1973). to Sol. SSSR. (1963). Mrs. (1964). experimental information source on source experimental information distances from distances Phys.. absorption J. thank and D. Chem. Fi:. BANDS (b) Phys.. however, absorption Chem. the structure E. E. 121.. E. of ser. 78. which M. rivrdoqo 34. band. McCumber. and McCumber. Dr. Phys. I. of E. obtaining phonons absorption AN corresponding in 56. fir., K1 Alshitz. Rodina for Rodina fhj-s.. 1682 F. PSB I. E. all 2814 S. SSSR. (1976). Sheka. Left.. 39. F. effect.” makes PSB with respect with trlu. Osadko (1963). impurity of 57. had Sheka, so in in Fk. (1972). absorption 1981 PL the 29. ser.,fiz.. 16. 5409 J. has that the the information on their help accompanying the this been fiwdoqo Lumin.. manuscript. (1975); exceeding 134 for of 1974 it M. Ix. (1972). been region numerous impossible case, (1974). SRC D. performed,26 systems to 39. (1974). AN interaction to in 8.349 Sturge. fch. Fi;. SRC 1900 neglected band processing, SSSR. PSB o, the too, of isotope rterdoqo 13. 40-50 (1975). (1974). helpful non- PSB may Php. 2653 are the are 22 SPI’. to 1 Downloaded By: [HEAL-Link Consortium] At: 15:59 14 January 2008 20. 23. 22. 21. 27. 24. 26. 25. 18. 19. 222 V. G. E. E. E. H. E. N. E. E. L. F. F. A. L. F. F. V. S. Bonadeo and Bonadeo Sheka, Sheka McCoy Sheka and Sheka Bokhenkov, Bokhenkov, Pawley. Loorits Rabinkina. in Usp.fi=. and and Ph-vs. Physics I. G. E. K. I. F. 1. P. Star. Taddei. Natkaniec. Natkaniec, 1. G. Terenetskaya. nauk, K. K. qfimpurify Rashba. and Rashba. Ross, Rebane. P. Sol. 92, J. MELETOV b. Ausrr. Chern. 542(1971). and E. 20, Trudy renfi-es M. 347 Fiz. E. E. J. Phps.. Rodina. and Rodina. F. F. Chcm.. IF (1967); trvrdqyo AND in Sheka, Sheka. AN crystals, 58.979 ESSR. 15. Phys. E. Fiz JETP, tela, 573 E. F. (1973). Tallin trerdogo Srat. 12, F. 32. (1962). SHEKA 70. Sheka 720 3 Sol. 1972. (1967). 1027 (1970). felu. h. (to (1976). p. 49. be 12, 431. 475 published). 3569 (1972). (1970).