DOCSLIB.ORG

2H -NMR Spectroscopy of Tunneling a Mm Onium

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
2H -NMR Spectroscopy of Tunneling a Mm Onium 2H-NM R Spectroscopy of Tunneling Ammonium Ion: General Site Symmetry Zdzislaw T. Lalowicz Institut für Physikalische Chemie der Universität, D-4400 Münster* and Institute of Nuclear Physics, Krakow Z. Naturforsch. 43a, 895-907 (1988); received July 19, 1988 2H-NMR powder spectra of tunneling ammonium-d4 ions are computed. A representation of the tunneling Hamiltonian is worked out in the basis of simple product spin wavefunctions. Secular parts of quadrupole and dipole Hamiltonians are taken into account. Examples of spectra are given for tunneling about one C2 or C3 axis, as well as for overall rotations in potentials of higher symmetry. Ranges of tunneling frequencies measurable from the spectra are given for each case. Characteristic shapes of the spectra allow recognition of various ground torsional level structures. Possible further applications and available data are discussed. PACS number 76.60 I. Introduction The NMR spectrum of a two proton system was calculated by G. E. Pake as early as 1948 [2], It is We consider systems of protons (I =1/2) or deute­ commonly called Pake's doublet, in which the separa­ rons (/ = 1) in solid, diamagnetic nonconducting com­ tion vd defines the dipole-dipole coupling constant pounds. In evaluating the spectra we restrict our­ Cd: vd = 3Cd = | f i y 2r -3 . The dipole-dipole inter­ selves to dipole-dipole or quadrupole interactions. The action is not modulated by reorientation jumps over n. dipole-dipole interaction of nuclear dipole moments Alternatively, jumps by | or rotation reduce the dou­ couples all spins of a system. The interaction of a blet splitting by The 2H-NMR spectrum of a rigid nuclear quadrupole moment with an electric field gra­ pair of deuterons resembles a Pake's doublet with a dient (EFG) has single particle character. Comparison separation 5 = | CQ, scaled up due to a bigger cou­ of protonated and deuterated systems allows for mak­ pling constant CQ = e2qQ h~l by two orders of ing use of the differences. Rigid systems of N protons magnitude. The spectrum is sensitive to jumps by n for show characteristic features in the NMR spectra for an inpressively wide range of exchange rates. The re­ N — 2, 3 and 4, whereas for higher N these features are sulting temperature dependence of the correlation lost [1]. On the other hand, any number of deuterons time was measured for heavy water molecules in in a rigid system gives a single doublet spectrum, pro­ Li2S04 D20 [3], vided no differences in the EFG exist. Andrew and Bersohn [4] supplied spectra for a three The study of molecular reorientation is based on its 7 = 1/2 triangular spin system. They consist of a cen­ specific averaging effect on the spectra. Inclusion of tral line flanked by two side components. The separa­ tunneling requires quantum mechanical treatment in tion of the sidepeaks is reduced by j on reorientation terms of space coordinates. The symmetrised wave- about the C3 symmetry axis. The methyl group CH3 functions of a multispin molecule may be labelled with has often been studied. Slow tunneling frequencies, the irreducible representations of the molecular sym­ vt < 0.1 MHz, are obtained from the spectra. Fast tun­ metry group. Except for diatomic molecules, states of neling rotation was found to give spectra identical to different symmetry are coupled by molecular hyper­ those of fast reorientation [5]. On the other hand, new fine interactions. This is of basic importance not only features were found recently in the NMR spectra of for spin conversion and relaxation processes, but also CD3, which allow identification of the type of motion for the spectra. [6], * Alexander von Humboldt Foundation Fellow 1985-87. The four spins of an ammonium ion form a tetrahe­ Reprint requests to Dr. Z. T. Lalowicz, Institute of Nuclear dron. The proton NMR lineshapes were treated theo­ Physics, ul. Radzikowskiego 152, 31-342 Krakow, Poland. retically for rigid NH4 by Bersohn and Gutowsky [7], 0932-0784 / 88 / 1000-907 $ 01.30/0. - Please order a reprint rather than making your own copy. 896 Z. T. Lalowicz • 2H-NMR Spectroscopy of Tunneling Ammonium Ion and the existence of spin isomers was pointed out by forms. Subsequent comparison with experimental Tomita [8]. Three motional cases may be distin­ spectra should then allow an identification of the GTL guished in a classical analysis of the NMR spectra: structure and in some cases also a determination of rigid ammonium ion, reorientation about its C3 or C2 the splittings. axes and isotropic reorientation [9], Experimental An analysis of the NMR spectra of ND4 tunneling work of Richards and Schaefer [10] revealed a surpris­ in a tetrahedral potential was already presented ing variety of proton spectra of ammonium com­ for single crystals [19] and powder samples [20], pounds at 20 K. These were later explained by tunnel­ Methods to measure tunnelling frequencies in the ing. Formal theoretical treatment and measurements 0.1 MHz < v, < 20 MHz range were outlined for at low temperatures followed [11-13]. The systemat- (ND4)2SnCl6 as an example, but the methods are also ics of the spectra according to the ground torsional applicable to other cubic compounds. These are char­ level (GTL) structure and numerous fits to the low acterised by the (A, 3T, E) GTL structure, and the temperature spectra were then supplied [9,14,15]. tunneling frequency is defined by A to 3T splitting. For one-dimensional rotation the torsional energy Most ammonium salts have a crystal symmetry lower levels may be calculated from the Mathieu equation than cubic. Lower symmetry barriers lead to other with a potential Vn = ^(1 — cos n a). In the case of GTL structures at low temperatures and to much ammonium ions a similar calculation may be applied more complex reorientation at higher temperatures. only to one-dimensional rotations about one of its Representative examples of both 2H-NMR single four C3 or three C2 symmetry axes. In general, howev­ crystal and powder spectra are given here for vari­ er, ammonium ions may experience potential barriers ous GTL structures. The sensitivity to vt is visualised of various symmetries and thus perform a more com­ and the identification of various GTL structures is plex motion, both in the tunneling rotation and re­ confirmed. orientation ranges. A very thorough discussion of a tetrahedron in a cubic crystalline field may be found II. Theoretical Principles in the paper by King and Hornig [16]. Smith devel­ oped numerical methods to obtain GTL structures for 1. Basic Definitions lower symmetry potentials [17], The complexity and The calculation of the NMR spectra is based in our convergence problems in the calculations, as well as treatment on the numerical solution of the eigenvalue idealized forms of potentials lead to poor agreement problem for a general Hamiltonian. In case of the with experimental data. NMR spectra of deuterated ammonium ions we can There is a need for more data on tunneling frequen­ limit ourselves to Zeeman, tunneling, quadrupole and cies and crystalline potentials. Except for a few cases dipole-dipole contributions: accessible to the high resolution inelastic neutron scattering (INS) [18], in all remaining cases the GTL je = jfz + + JTq 4- #eD. (i) structure can be determined for NH4 from the NMR Zeeman and tunneling Hamiltonians represent zeroth spectra only. NMR remains the only method in the order energies in spin and space coordinates, respec­ ND4 case, as tunneling splitting is always reduced tively. Quadrupole and dipole interactions, bilinear in beyond the resolution of INS methods. both coordinates, are acting as perturbations. We are going to apply here a group theoretical We take as starting representation (21 +1)4 = 81 approach to the GTL structure of ND4 . Expressions simple product wavefunctions | /1/I^z^z)- Here we for GTL energy sublevels are written in terms of pa­ will use the notation I[z = a, 0, ß for </^> = 1 ,0 ,- 1, rameters representing tunneling frequenices about respectively, and the superscript /' will be recognized separate C3 and C2 symmetry axes. The tunneling from the position. This is the main difference with parameters depend on the respective cross sections of respect to a previous paper [21], where eigenfunctions a three-dimensional potential. Neither potentials nor of I = Y,Ui\ and were used as a basis from the tunneling splittings are known, so we use free tunnel­ i ing parameters. This makes the problem of the NMR beginning. spectra of tunneling ND4 ions tractable. The evolu­ We may write the Zeeman Hamiltonian as tion of the spectra on the splittings within the libra­ Jfz = - y DhB0 I I'z. (2) tional ground state multiplet supplies the master i = 1 897 897 Z. T. Lalowicz • 2H-NMR Spectroscopy of Tunneling Ammonium Ion fills the diagonal submatrices of the general Hamilto­ The magnetic quantum number M = X <7z> labels i = 1 nian with offdiagonal terms. As the contribution of the the Zeeman energy levels, and the wavefunctions may Hamiltonian (6) to the eigenenergies of the system is be grouped into respective manifolds. A matrix of relatively small and spoils the clarity of the quadru­ the Hamiltonian (1) can be structured accordingly, pole Hamiltonian symmetry, we will henceforth ne­ and we get diagonal submatrices of the dimensions glect it in the discussion. In the numerical calculations l x l (M = +4), 4x4(M = ±3), 10xl0(M = ±2), presented further on, the complete Hamiltonian has 16x16(M = ± 1), 19 x 19(M = 0)(compareTable 1 in always been used. [22]). The quadrupole interaction Hamiltonian describ­ 2. Tunneling Hamiltonian Representation ing the coupling between a non-spherical nuclear charge distribution and the EFG at the nucleus may The ammonium ion has forms a regular tetrahe­ be written as a product of a Cartesian quadrupole dron with the nitrogen in the center.
Load more

Recommended publications
  • Preparation of Inorganic–Organic Composites As Acid–Base Catalysts Using Hca2nb3−Xta Xo10 and Quaternary JCS-Japan Onium Salts
    Journal of the Ceramic Society of Japan 128 [1] 51-55 2020 -Japan DOI http://doi.org/10.2109/jcersj2.19119 JCS NOTE Preparation of inorganic­organic composites as acid­base catalysts using HCa2Nb3¹xTaxO10 and quaternary onium salts Masataka OGASAWARA1,³, Takuto BAN2, Kanji SAITO1,3 and Sumio KATO1 1 Graduate School of Engineering Science, Department of Materials Science, Akita University, 1–1 Tegata gakuen-machi, Akita 010–8502, Japan 2 Graduate School of Engineering and Resource Science, Department of Applied Chemistry, Akita University, 1–1 Tegatagakuen-machi, Akita 010–8502, Japan 3 Kagami Memorial Research Institute for Materials Science and Technology, Waseda University, 2–8–26 Nishiwaseda, Shinjuku-ku, Tokyo 169–0054, Japan Inorganic­organic composites have been prepared using Dion­Jacobson-type layered perovskite compounds as base catalysts. Dodecyltributylphosphonium bromide (C12TBPBr), dodecyltriphenylphosphonium bromide (C12TPPBr), or dodecyltrimethylammonium chloride (C12TMACl) were used as the organic species of the + + + inorganic­organic composite. It was suggested that C12TBP ,C12TPP ,orC12TMA were intercalated by ion- + exchange with interlayer H of HCa2Nb3O10. The acid­base reaction was evaluated by consecutive deacetalization­Knoevenagel reactions. The product of the second-step reaction of the inorganic­organic composite catalysts was obtained, which suggested that the composites were acid­base bifunctional materials. For composites prepared using HCa2Nb3¹xTaxO10 (x = 1, 2, and 3) as inorganic species, the base catalytic activity decreased with decreasing fraction of organic species. Therefore, the hydrophobicity of the layered compounds affected the catalytic activity of the composite. Various catalysts should be prepared using reported layered perovskite-type compounds having various compositions. ©2020 The Ceramic Society of Japan.
    [Show full text]
  • LD2668T41961L36.Pdf
    CARBC^IA-CONTAINIMG CGHFOUKDS PRODUCED BI THE PILE-SEOTRQH IRRADIATIGH OP CYAHOGUANIDIIE THOMAS WILLIAM LAPP * B.A., Co* College, 1959 A MAS TBI'S THESIS . submitted in partial fulfillment of the requirements for the degree MASTER 07 SCIENCE Department of Chemistry KANSAS STATE UNIVERSITY Manhattan, Kansas 1%1 TABLE OP COHTKHTS INTRODUCTIOU 1 Theoretical Considerations 3 Previous llH(n,p)cU studies 10 EXPERIMENTAL 21 Sample Preparation. 21 Irradiation of the Cyanoguanidine Sample. • 21 Analysis of the Irradiated Sample 23 Total Carbon-U Activity 25 Chemical Separations 25 Radiochemical Counting Techniques 31 RESULTS AND DISCUSSION 37 Distribution of the Carbon-14 Recoil Atom 40 Radiocarbon Product Distribution 46 SUMMARY 50 ACKNOWLEDGMENTS 51 REFERENCES 52 t nmtCLXTroi In a flux of thermal neutrons, nitrogen atone undergo the nuclear trine- formation NH(n>p)cH. in normal pile-neutron irradiations, the compound to be Irradiated is also subjected to gamma radiation. Both the gamma radia- tion and the nuclear reactions initiated by the neutrons are capable of supplying energy to promote chemical reactions which normally would occur only at elevated temperatures. Collins and Calkins (6) have estimated the average energy of the gamma rays in the Oak Ridge graphite reactor to be approximately 1 Mev. Few nuclear reactions are initiated by the absorption of gamma rays at this photon energy and thus, the important nuclear reactions are those produced by the neutrons. The eyanoguanidine molecule is interesting for studying the chemical consequences produced by the nuclear transformation NU( n ,p)cH for two reasons (1) Within the eyanoguanidine molecule, the nitrogen atoms are bound to carbon atoms by three different types of bonding: single, double and triple bonds.
    [Show full text]
  • The New Look in Oil-Mud Technology
    DISPERSIBLE COLLOIDS The New Look in Oil-Mud Technology JAY P. SIMPSON MEMBER AIME BAROID DIV., NATIONAL LEAD CO. Downloaded from http://onepetro.org/jpt/article-pdf/13/12/1177/2213517/spe-150-pa.pdf by guest on 27 September 2021 J. C. COWAN HOUSTON, TEX. A. E. BEASLEY, JR. Abstract tributed to the general inflexibility of the systems. This inflexibility resulted primarily because one basic component Liquids having oil as the continuous phase long have was used in an attempt to arrive at all mud properties. been recognized as desirable for drilling and completing These oil systems can be compared with the early water­ under certain conditions. Performance limitations, high base muds. costs and inconvenience of handling, however, have kept these oil muds from becoming accepted for widespread, Water-base mlfds in the early years of drilling depended general use. upon bentonite for rheological properties, suspension of solids and filtration control. As was learned with these As previously used, the muds consisted of a bodying earlier clay-water systems, one basic component cannot agent for oil, or primary emulsifier of water in the oil, and by itself provide all of ideal drilling-fluid properties. Today a series of supplementary additives to modify that principal each water-base drilling-fluid property can be controlled component. In recent years a new approach to oil muds with an exactness that was not believed possible even 10 has been taken. Oil-dispersible colloids have been developed years ago. Water-base muds are prepared to have certain to perform specific functions in oil without dependence properties to serve specific purposes, some examples of upon thickening of the oil or emulsification of water.
    [Show full text]
  • Pdf 290.76 K
    Iranica, Vol. 14, No. 4, pp 297{302 Scientia c Sharif University of Technology, August 2007 y-Supp orted Quaternary Ammonium and Cla Cations in Triphase Catalysis and Phosphonium E ect of Cosolvent in Catalytic Activity the 1 1 1 B.L. Cutts D. Dutko and S. Khazaeli , Shab estary , N. this research, a naturally o ccurring clay mineral, hectorite, was used as the supp ort for several In ry ammonium and phosphonium cations to measure and compare their catalytic activity quaterna a triphase catalytic system. The intercalation of the catalysts in the clay has the advantage in easy catalyst recovery; the catalyst can b e removed by a simple separation technique, such of ltration or centrifugation, up on completion of the reaction. The rate of conversion of n- as yl bromide to n-butyl chloride was measured in the presence of two classes of phase transfer but Quaternary ammonium and quaternary phosphonium cations. The rate of the reaction catalyst: as measured for the biphase reactions (no supp orting clay) and for the triphase catalytic system w supp orting clay). The results have shown that quaternary phosphonium catalysts ar e (with more reactive than the corresponding quaternary ammonium catalysts. It wa s also somewhat that the intercalated catalysts could be used several times b efore losing their catalytic found y. Also, a remarkable increase in catalytic activity has b een observed using a co-solvent. activit wever, it app ears that there is a limit for the co-solvent concentration to b e e ective. Ho Based on this technique, synthetic metho ds phases.
    [Show full text]
  • Download Author Version (PDF)
    PCCP Accepted Manuscript This is an Accepted Manuscript, which has been through the Royal Society of Chemistry peer review process and has been accepted for publication. Accepted Manuscripts are published online shortly after acceptance, before technical editing, formatting and proof reading. Using this free service, authors can make their results available to the community, in citable form, before we publish the edited article. We will replace this Accepted Manuscript with the edited and formatted Advance Article as soon as it is available. You can find more information about Accepted Manuscripts in the Information for Authors. Please note that technical editing may introduce minor changes to the text and/or graphics, which may alter content. The journal’s standard Terms & Conditions and the Ethical guidelines still apply. In no event shall the Royal Society of Chemistry be held responsible for any errors or omissions in this Accepted Manuscript or any consequences arising from the use of any information it contains. www.rsc.org/pccp Page 1 of 12Journal Name Physical Chemistry Chemical Physics Dynamic Article Links ► Cite this: DOI: 10.1039/c0xx00000x www.rsc.org/xxxxxx ARTICLE TYPE Estimating the Binding Ability of Onium Ions with CO 2 and π Systems: A Computational Investigation M. Althaf Hussain, A. Subha Mahadevi and G. Narahari Sastry* Manuscript Received (in XXX, XXX) Xth XXXXXXXXX 20XX, Accepted Xth XXXXXXXXX 20XX 5 DOI: 10.1039/b000000x Density functional theory (DFT) calculations have been employed on 165 complexes of onium ions + + + + (NH 4 , PH 4 , OH 3 ,SH 3 ) and methylated onium ions with CO 2, aromatic (C 6H6) and heteroaromatic (C 5H5X, X = N, P; C 4H5Y, Y = N, P; C 4H4Z, Z = O, S) systems.
    [Show full text]
  • A Probabilistic QCD Picture of Diffractive Dissociation and Predictions for Future Eics
    A probabilistic QCD picture of diffractive dissociation and predictions for future EICs Anh Dung Le Based on: ADL, Mueller & Munier, PRD 103 (2021) 054031 ADL, Mueller & Munier, ar iv:2103"100## ADL, arXi!:2103"0$$24 Presen%ed at RPP2021 MO I!A ION + A QCD pi.%ure for diffra.%ion and partonic le!el + Predic%ions a% /u%ure ele.%ron-ion colliders (EICs) 4'ser!a'le of interes%: Rapidity-gap distribution! Diffraction at #ERA$ A large angular ga& obser!ed( Large ra&idity ga& (LRG) 2 CON E" ) 3" DIS in dipole 6odel and diffra.%ion 33" Diffra.%i!e disso.ia%ion of oniu6: a proba'ilis%ic ,CD &ic%ure 333" Diffra.%ive disso.ia%ion a% /u%ure EICs 3 QCD dipole *odel for DI) 7ir%ual photon probes nu.leus !ia a quark-an%iquar9 .olor single% dipole (oniu6) Dipole /a.%oriza%ion: Proba. of the splitting virtual photon → dipole :;: momen%um frac%ion of &hoton carried b) quar9 (or an%i8uark)] 4 Diffractive dissociation of virtual p+oton 2!ol!ed s%a%e 'y Q-D radiati!e e6issions Photon disso.iated to a se% o/ &arti.les (X) > angular gap in de%e.%ors =u.leus ke&% in%ac% 5 Diffractive dissociation of onium 6 Color dipole evolution: )oft-gluon e*issions I0 I0 r Large N 1 ?igh-ra&idi%) e!olu%ion I . I 2 r 2 Transverse position rk r2 space I1 I1 Large nu6'er o/ colors (N.) li6i%: gluon ≃ ;ero1si;e quar91an%i8uark pair @ one1gluon e6ission ≃ (1A 2) di&ole bran.hing (L4; soH1gluon a&&roI.) Boos%ing to high rapidi%y B: 1 Bran.hing re&ea%ed (and inde&enden%) → 'ran.hing &ro.ess 1 Coc9 s%ate of oniu6 is a se% of di&oles wi%h random si;es {r9F A random num'er densi%) n(r9) Each event recorded in a detector corresp.
    [Show full text]
  • SANTA CRUZ INSTITUTE for PARTICLE PHYSICS LIST of PREPRINTS SCIPP # 1. Finite Size Scaling and Asymptotic Freedom of the SU(2)
    SANTA CRUZ INSTITUTE FOR PARTICLE PHYSICS LIST OF PREPRINTS SCIPP # 1. Finite Size Scaling and Asymptotic Freedom of the SU(2) Lattice Gauge Model, M. Nauenberg, T. Schalk and R. Brower, Phys. Rev. D24:548 (1981) 81/1 2. Cosmic Ray Trigger Circuit for Large Solenoidal Particle Detectors, A. Seiden, P. Shaffer and J. Warner, NIM 193:597 (1982) 81/2 3. Elastic Photon-Photon Scattering in the 50-130 GeV Range, A.M. Breakstone et al., Phys. Rev. Lett. 47:1778 (1981) 81/3 4. Quasi-Elastic Omega Photoproduction at 50-130 GeV, A.M. Breakstone et al., Phys. Rev. Lett. 47:1782 (1981) 81/4 5. Large Drift Chambers with a Multi-Wire Cell Design, F. Grancagnolo and A. Seiden 81/5 6. A Large-Solid-Angle Spectrometer for High Energy Electrons and Photons, A.M. Breakstone, C.A. Heusch and A. Seiden, NIM 211:209 (1983) 81/6 7. The SU(2) Adjoint Higgs Model, R.C. Brower et al., Phys. Rev. D25:3319 (1982) 81/7 8. Some Ideas on a Central Tracking Chamber for the SLAC Linear Collider, A. Seiden, Proceedings of the 2nd 81/8 TRISTAN Physics Workshop, KEK, Tsukuba, Japan; Ed. Y. Unno, KEK 82-1, p.466 (May 1982) 9. Heavy Flavor Production from Photons and Hadrons, C. Heusch, Presented at the SLAC Summer Institute 82/9 on Particle Physics, 1981. 10. Wide Angle Secondaries Produced by `Beamstrahlung' Interactions, D.B. Smith (SLC Report). 82/10 11. Central Tracking Chamber for SLC, A. Seiden (SLC Report) 82/11 12. Tradeoffs in Drift Chamber Design, A.
    [Show full text]
  • Deep-Inelastic Onium Scattering
    DAPNIA/SPP 95-15 SPhT-T95-090 Deep-Inelastic Onium Scattering H.Navelet1, R.P eschanski1,Ch.Royon2 1- Service de Physique Th´eorique, Centre d’Etudes de Saclay F-91191 Gif-sur-Yvette Cedex (France) 2- DAPNIA - SPP, Centre d’Etudes de Saclay F-91191 Gif-sur-Yvette Cedex (France) Abstract: Using the colour dipole approach of the QCD per- turbative (BFKL) Pomeron exchange in onium-onium scattering, we compute the cross section for small but hierarchically different onium sizes. A specific term dependent on the size-ratio is gener- ated. In deep inelastic onium scattering it appears as a scaling- violation contribution to the quark structure function near the BFKL singularity. We find that the extension of the formalism for deep inelastic onium scattering to the proton structure func- tion provides a remarkably good 3-parameter fit to HERA data at small x with a simple physical interpretation in terms of the dipole formulation. 1 Recently, a dipole model approach to the QCD computation of onium- onium scattering from the perturbative resummation of leading logarithms has been proposed[1, 2, 3]. In this framework, each onium state describes a small (i.e. massive) colour-singlet quark-antiquark pair whose infinite mo- mentum wavefuntion is itself composed of colour dipoles at the moment of the interaction. These onia interact locally in impact-parameter space via 2-gluon exchange between the component dipoles. The overall total cross-section has been shown to reproduce the well-known[4] QCD Pomeron exchange (BFKL) due to leading log 1/x resummation. It is thus tempting to try and apply this formalism to the deep-inelastic scattering off protons and more specifically to the proton structure function measured at HERA[5].
    [Show full text]
  • Onium Method for Extraction and Spectrophotometric Determination of Zn (Ii) and Co (Ii)
    IMPACT: Journal of Research in Applied, Natural and Social Sciences (IMPACT: JRANSS) ISSN(E): Applied; ISSN(P): Applied Vol. 1, Issue 2, Dec 2015, 41-54 © Impact Journals ONIUM METHOD FOR EXTRACTION AND SPECTROPHOTOMETRIC DETERMINATION OF ZN (II) AND CO (II) SHAWKET KADHIM JAWAD & JIHAN RAZZAQ MUSLIM Department of Chemistry, College of Education for Girls, Iraq ABSTRACT UV-Vis. spectrum for complexes of Zn (II) and Co (II) extracted according to onium system from acidic HCL solution by use 2,4-dimethylpentan-3-one (2,4-DMP) as onium complex was (262nm) for Zn(II) but onium complex for Co(II) was (243nm), this method show need 0.5M HCL for extraction Zn 2+ and 0.8M HCL for Co 2+ , as well giving obey to Beer-Lambert relation at the (1-20µg) for Zn 2+ and (1-50µg) for Co 2+ . The onium complex extracted have structure + - + - H(H 2O)(2,4-DMP) 3 ;HZnCl 4 , H(H 2O)(2,4-DMP) 3 ;HCoCl 4 . This method obey to Beer-Lambert relation at the range (1-20µg) for Zn 2+ ε=16893.56L.mol -1.cm -1, D.L=6.33×10 -6µg/Ml, RSD%=0.0069µg/Ml, Sandell’s sensitivity=3.87×10 - 9µg/cm 2 and (5-50µg) for Co 2+ , ε=8918.77L.mol -1.cm -1, D.L=3.38×10 -5 µg/Ml, RSD%=0.00664µg/Ml, Sandell’s sensitivity=7.33×10 -9µg/cm 2. As well as this research involved many studies and apply for determination Zn 2+ and Co 2+ in different samples.
    [Show full text]
  • Diffractive Dissociation in Future Electron-Ion Colliders
    1 INTRODUCTION Diffractive dissociation in future electron-ion colliders Anh Dung Le?, CPHT, CNRS, École polytechnique, IP Paris, F-91128 Palaiseau, France * [email protected] August 2, 2021 Proceedings for the XXVIII International Workshop on Deep-Inelastic Scattering and Related Subjects, Stony Brook University, New York, USA, 12-16 April 2021 doi:10.21468/SciPostPhysProc.? Abstract We study diffractive scattering cross sections, focusing on the rapidity gap distribution in realistic kinematics at future electron-ion colliders. Our study consists in numerical solu- tions of the QCD evolution equations in both fixed and running coupling frameworks. The fixed and the running coupling equations are shown to lead to different shapes for the rapid- ity gap distribution. The obtained distribution when the coupling is fixed exhibits a shape characteristic of a recently developed model for diffractive dissociation, which indicates the relevance of the study of that diffractive observable for the partonic-level understanding of diffraction. 1 Introduction Single diffractive dissociation in electron-hadron collisions is defined to be the scattering process in which the virtual photon mediating the interaction fluctuates into a set of partons part of which goes in the final state while the hadron remains intact, leaving a large rapidity gap between the latter and the slowest produced particle. The rapidity gap characterization of diffractive events is manifested in collision experiments by the existence of a large angular sector in the detector arXiv:2107.14511v1 [hep-ph] 30 Jul 2021 with no measured particle. Such events were first observed in electron-proton collisions at DESY HERA [1,2 ], and their detailed analysis is one of goals of the construction of future electron-ion colliders [3–5].
    [Show full text]
  • Investigating Extreme Ultraviolet Radiation Chemistry with First-Principles Quantum Chemistry Calculations
    Investigating extreme ultraviolet radiation chemistry with first-principles quantum chemistry calculations a,b c c Jonathan H. Ma, Han Wang, David Prendergast, a,d a, Andrew Neureuther, and Patrick Naulleau * a Lawrence Berkeley Laboratory, Materials Sciences Division, Center of X-Ray Optics, Berkeley, California, United States b University of California Berkeley, Department of Physics, Berkeley, California, United States c Lawrence Berkeley Laboratory, Molecular Foundry, Berkeley, California, United States d University of California Berkeley, Department of Electrical Engineering and Computer Science, Berkeley, California, United States Abstract. In extreme ultraviolet (EUV) lithography, chemistry is driven by secondary elec- trons. A deeper understanding of these processes is needed. However, electron-driven processes are inherently difficult to experimentally characterize for EUV materials, impeding targeted material engineering. A computational framework is needed to provide information for rational material engineering and identification at a molecular level. We demonstrate that density func- tional theory calculations can fulfill this purpose. We first demonstrate that primary electron energy spectrum can be predicted accurately. Second, the dynamics of a photoacid generator upon excitation or electron attachment are studied with ab-initio molecular dynamics calcula- tions. Third, we demonstrate that electron attachment affinity is a good predictor of reduction potential and dose to clear. The correlation between such calculations and experiments suggests that these methods can be applied to computationally screen and design molecular components of EUV material and speed up the development process. Keywords: extreme ultraviolet lithography; extreme ultraviolet exposure chemistry; photoacid generator chemistry; radiation chemistry; extreme ultraviolet fundamentals. 1 Introduction With the introduction of extreme ultraviolet (EUV), electron-driven processes in photoresists 1 become relevant.
    [Show full text]
  • Inorganic Seminar Abstracts
    C 1 « « « • .... * . i - : \ ! -M. • ~ . • ' •» »» IB .< L I B RA FLY OF THE. UN IVERSITY Of 1LLI NOIS 546 1^52-53 Return this book on or before the Latest Date stamped below. University of Illinois Library «r L161— H41 Digitized by the Internet Archive in 2012 with funding from University of Illinois Urbana-Champaign http://archive.org/details/inorganicsemi195253univ INORGANIC SEMINARS 1952 - 1953 TABLE OF CONTENTS 1952 - 1953 Page COMPOUNDS CONTAINING THE SILICON-SULFUR LINKAGE 1 Stanley Kirschner ANALYTICAL PROCEDURES USING ACETIC ACID AS A SOLVENT 5 Donald H . Wilkins THE SOLVENT PHOSPHORYL CHLORIDE, POCl 3 12 S.J. Gill METHODS FOR PREPARATION OF PURE SILICON 17 Alex Beresniewicz IMIDODISULFINAMIDE 21 G.R. Johnston FORCE CONSTANTS IN POLYATOMIC MOLECILES 28 Donn D. Darsow METATHESIS IN LIQUID ARSENIC TRICHLORIDE 32 Harold H. Matsuguma THE RHENI DE OXIDATION STATE 40 Robert L. Rebertus HALOGEN CATIONS 45 L.H. Diamond REACTIONS OF THE NITROSYL ION 50 M.K. Snyder THE OCCURRENCE OF MAXIMUM OXIDATION STATES AMONG THE FLUOROCOMPLEXES OF THE FIRST TRANSITION SERIES 56 D.H. Busch POLY- and METAPHOSPHATES 62 V.D. Aftandilian PRODUCTION OF SILICON CHLORIDES BY ELECTRICAL DISCHARGE AND HIGH TEMPERATURE TECHNIQUES 67 VI. £, Cooley FLUORINE CONTAINING OXYHALIDES OF SULFUR 72 E.H. Grahn PREPARATION AND PROPERTIES OF URANYL CARBONATES 76 Richard *• Rowe THE NATURE OF IODINE SOLUTIONS 80 Ervin c olton SOME REACTIONS OF OZONE 84 Barbara H. Weil ' HYDRAZINE BY ELECTROLYSIS IN LIQUID AMMONIA 89 Robert N. Hammer NAPHTHAZARIN COMPLEXES OF THORIUM AND RARE EARTH METAL IONS 93 Melvin Tecotzky THESIS REPORT 97 Perry Kippur ION-PAIR FORMATION IN ACETIC ACID 101 M.M.
    [Show full text]