BRITISH CHEMICAL ABSTRACTS A —PURE CHEMISTRY MARCH, 1936. General, Physical, and Inorganic Chemistry. Absorption spectrum of hydrogen. II. The Excitation of the auroral green line by meta­ D state in the term scheme of hydrogen from stable nitrogen molecules. J. K a p la n (Physical photographs of H 9 and D2. H. B e u t le r , A. Rev., 1936, [ii], 49, 67— 69; cf. A., 1934, 827).— Deubner, and H. 0 . J ü n ger (Z. Physik, 1935, 98, Jhc excitation in tubes which show the two new 181—197; cf. A., 1935, 1291). ' A. B. D. C. afterglow spectra of N2 is described. The conditions Ground state of (H2), the molecular ion (H2<), of excitation are compared with those in the night- and wave mechanics. 0. W. Richardson (Proc. sky and in the aurora borealis, in which cases, it is Roy. Soc., 1935, A , 152, 503— 514).— The agreement suggested, the LSq state of 0 which is responsible between the vals. of the fundamental consts. of the for the green line is produced by collisions of O atoms ground state of the H 2 mol. (i) as determined by and metastable N2 mols. in the A 8S state. experiment, and (ii) as calc, by wave mechanics, is N. M. B. discussed. The properties of the mol. ion (H2+) Hopfield’s Rydberg series and the ionisation as predicted by wave mechanics are compared with potential and heat of dissociation of nitrogen. those predicted empirically from a study of various R. S. M u llik e n (Physical Rev., 1934, [ii], 46 144 - excited states of (Ii2). ' . ' L. L. B. 146; cf. A., 1931, 1343). L. S. T. Fine structure of Da with increased resolution. Predissociation of the oxygen molecule. P. J R. C. Williams and R . C. G ibbs (Physical Rev., F lo r y (J. Chem. Physics, 1936, 4, 23— 27).— Opticai 1936, [ii], 4 9 , 40; cf. this vol.. 127).—A correction. data for 0 2 are interpreted as indicating that the N. M. B. initial process in the photochemical reactions of 0 2 Energy states of doubly excited helium. T. Y. due to light in the region of Schumann-Runge band Wu (Physical Rev., 1934, [ii], 4 6 , 239). L. S. T. absorption is the formation of normal 3P atoms by predissociation rather than the reaction of an optically Doubly-excited states in helium. F. G. Fender excited mol. with a normal, mol., as hitherto supposed and J. P. V in ti (Physical Rev., 1934, [ii], 46 , 77— M. S. B. 78)' L. S. T. Arc spectra of fluorine and potassium. B. Absorption of fluorspar [transmitted] ultra­ E d lü n (Z. Physik, 1936, 98, 445—460).— 85 F i violet light by carbon black, gold, and rhombic lines between 6000 and 9500 A. are tabulated. sulphur. G. R a th e n a u (Physica, 1936, 3 , 42— 60). A. B. D. C. 0 black has an absorption max. at approx. 2500 A., Intensity measurements in the spectra of and a min. at approx. 1700 Ä .; Au has an absorption neon and argon excited by electron collision. niax. at about the latter A. S layers, transparent to O. H errm a n n (Ann. Physik, 1936, [v], 25, 143— n tra-violet light, were made by vaporisation in vac. 165).—Efficiency determinations for the excitation o?J;0»a k'aF2 plate at —80°. S absorbs at about of the Xe and A spectra by electron collision have been A., and there is another band at 1800 A. The made by an abs. method. The scattering of electrons results are discussed in relation to the at. and mol. and their angular distribution are taken into account. spectra, A . J . M. The abs. yield and excitation probabilities for 54 A Light yield in the nitrogen spectrum excited lines, and the excitation functions for 52 A and 16 Ne f ™ ° n collision. O. Herrmann (Ami. Physik, lines are recorded. Comparison of the abs. yields of 7 36, [v], 25, 166—•184).—-The excitation function X e and 7 A lines belonging to the same term shows no simple connexion between the two gases. vi ,, ,neSa^ve bands of the X spectrum and the abs. } ie d for 3 negative and 5 of the second positive A. J. M. gioup of N2+ and X 2 band spectra have been deter- Intensity distribution of neon lines. E. Lau (Physikal. Z., 1936, 37, 110).—Polemical against mmed- " A. J. M. Schütz el al. (A., 1935, 907). A. J. M. Dependence of intensities of rotation lines of band on the conditions of excitation. 0. [Intensity distribution of neon lines.] W. R errsiann (Physikal. Z., 1936, 37, 100— 103).— S ch ü tz (Physikal. Z., 1936, 37, 110— 111).— A reply to the above. A. J. M. ^ IC Iincs in the II branch of the J ,an °.f t*le negative X, group at 3914 A. have Absolute transition probability of potassium. ... -1 determined for excitation with electrons of E. F. M. van d e r H e ld and J. H. H eierm an (Physica, various velocities. A. J. M. 1936, 3, 31— 41).— The abs. intensity of light emitted 261 I {a, b) 262 BRITISH CHEMICAL ABSTRACTS.— A. by K atoms in a C2H2-air flame, the flame temp., New “ bright” method for investigation of and the no. of emitting particles have been deter­ the Stark effect with a homogeneous field. W. mined, and the abs. transition probabilities of the Stettbtng and J. A. S c h a e d e r (Ann. Physik, 1930, resonance lines of Iv calc. The abs. transition prob­ [v], 25, 97— 123).— The method enables very bright abilities were also obtained for the sharp and diffuse spectra to be produced in a measurable homogeneous series by photographic comparison with the resonance electric field, and makes it possible to examine the lines, using light of known colour temp. A. J. M. Stark effect of some atoms and mols. which are difficult to excite by other methods. A. J. M. Arc spectrum of rubidium. K. W. M e is s n e r Analysis and interpretation of the nebular (Z. Physik, 1935, 98, 353—354). A. B. D. C. spectrum of Nova Herculis. M. B lo c h and J. Fine structure in the (2D) series limit terms D u e a y (Compt. rend., 1935, 201, 1463— 1465).— o f the 1+ sp ectru m . S. T o la n s k y (Proc. Physical Lines are due to H i, He I, He n , O n , N n , C ii, Soc., 1936, 48, 49— 56; cf. A., 1935, 137).— Classi­ 0 m , N m , and probably C m . T . G. P. fications and fine-structurc data are tabulated for Absorption of monochromatic X-ray beams, I +, and fine structure analyses of 14 lines of the -D of wave-length in the region 50—20 X units, in system and interval factors for 12 terms are given. lead, tin, copper, and iron. J. R e a d (Proc. Roy. Large interval factors associated with the 5d electron Soc., 1935, A , 152, 402—417; cf. A., 1934, 577).— terms of the iS and 2Z> systems are correlated with A curve relating the absorption coeff. of Pb and the observations for Sn rt, and are due to perturbation Xhas been obtained. The photo-electric absorption by torms with large fine structure. Two types of coeffs. calc, from this are 7— 20% > corresponding perturbation in the fine structures arc observed. vals. obtained from Gray’s empirical law (A., 1931, 1 N. M. B. 281). L. L. B. Nuclear spin of iodine. II. Fine structure in Fluorescence X-ray yields from K shells of the arc spectrum and a fine structure perturb­ atom s. R. J. Stephenson (Physical Rev., 1934, a tion effect. S. T o la n s k y (Proc. Roy. Soc., 1935, [ii], 46, 73—74).—A criticism and a revision of vals. A, 152, 663—672; cf. A., 1935,137).—The fine struc­ (cf. A., 1934, 577). L. S. T. tures of 13 of the classified lines of the I arc spectrum Dose measurement of very soft X-rays. E. (6300— 4760 Á.) have been measured. The nuclear W il h e lm y (Pliysikal. Z., 1936, 37, 103— 107).—The spin is confirmed as 5/2. The 6s4P5/2 is perturbed. method employs an ionisation chamber of sufficient L. L. B. length to absorb the rays almost completely. Absorption spectra of cerium, neodymium, b A. J. M. and samarium. P. W. P aul (Physical Rev., 1936, Effects of chemical binding on the X-ray [ii], 49, 156— 162; cf. King, this vol., 2).—Data for Iiali2 doublet lines of sulphur studied with a XX and intensities of 600 Ce, 450 Nd, and 1500 Sm two-crystal spectrometer. L. G. P a r r a t t (Physi­ lines are tabulated in the region 12,000— 2500 A. cal Rev., 1936, [ii], 49, 14— 16).— Using FeS, Cu2S, N. M. B. MgS04, BaS04, and PbS targets, ionisation curves Absolute intensities in the spectrum of a were recorded, and effects of binding on X, on the low-pressure quartz mercury-vapour discharge a, a2 separation, and on the doublet contour were burner. A. J. M a d d o c k (Proc. Physical Soc., 1936, measured. The X shift of the S A a ,i2 lines from 48, 57—62).—Abs. intensities of tho main XX in the sulphates to sulphides was observed in the process of range 6000—2400 A.