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British Chemical Abstracts BRITISH CHEMICAL ABSTRACTS A.-PURE CHEMISTRY FEBRUARY, 1934. General, Physical, and Inorganic Chemistry. Ground state of the hydrogen molecule. and 2750 mji., and a new band at 1261 mix is recorded. H. M. J a m e s and A. S. C o o l id g e (J . Chem. Physics, The complete spectrum, including infra-red bands, 1933, 1, 825—835).—Mathematical. The method is represented by a linear formula involving the of Hylleraas for the He atom is extended to the frequencies 793 and 1307 mm.-1 and the vibrational H, mol. N. M. B. frequency of 0 2. Certain combination bands are Relative intensities of atomic spectral lines ascribed to (02)2. A. B. D. C. from a hydrogen discharge tu b e. W. W. J a c k s o n Wave-lengths of the red lines of neon and their (Phil. Mag., 1934, [vii], 17, 33—53).—H a varies use as secondary standards. C. V. J a c k s o n parabolically and II$ and P„ vary linearly with the (Proc. Roy. Soc., 1933, A, 143, 124—135).—Direct discharge current at const, pressure and p.d. across comparisons of the wave-lengths of the red lines the tube. Relative transition probabilities have of Nc with the primary standard show that, for resolv­ been calc. H. J . E. ing powers > 250,000, the Ne lines have const, wave­ lengths. With lower resolving powers, however, the Negative sections of the cold-cathode glow wave-lengths become systematically lower, until a discharge in helium. K. G. Emeléus, W. L. min. is reached at about 100,000. This is caused B r o w n , and H. McN. C o w a n (Phil. Mag., 1934, by blending of the weak satellite (due to Ne22) with [vii], 17, 146— 160).—Discharge characteristics are the main line. A table of corrections to be applied described. H. J. E. to the standard Ne wave-lengths when used with Stark effect with the helium 5876 line with apparatus of low resolving power is given. high resolution. R. R it s c h l (Physikal. Z., 1934, L. L. B. 35, 53).—The Stark effcct with the He 5876 line has Natural width of neon lines in the visible been investigated with high resolution to discover the spectrum . I. W. S c h ü t z . II. H. S c h il l b a o h behaviour of each component in the electric field. (Ann. Physik, 1933, [v], 18, 705—720, 721—745).— A. J. M. I. An experimental test of the quantum theory Measurement of arc temperature from C2 applied to the natural width of Ne lines is proposed bands. Transition probability of vibrational and the theory of it discussed. The difference between transitions. D. T . J. T e r H o r st and C. K r y g s m a n the results obtained by application of the old and (Physica, 1933, 1, 114— 118).—From the intensities new (Dirac-Weisskopf-Wigner) quantum theories is of the C2 rotation bands the temp, of an arc is calc, that according to the latter, within a group of Ne lines as 6000° abs., in agreement with the val. calc, from with a common initial level the width of the lines due CN bands. Assuming the same temp, for the to transition to the unstable s2 level should be > vibrational bands, the ratio of transition prob­ that of lines due to transition to the metastable s3 abilities agrees with theory (Wurm, Z. Astrophys., and s5 levels. 1932, 5, 260). " J. W. S. II. An account of the experimental work in New terms in the spectra of N in, N iv, N v, connexion with the above is given, involving the O h i, O iv , and O v. W. M. Ca d y (Physical Rev., determination of the intensity distribution in the 1933, [ii], 44, S21—825; cf. Edlén, A., 1933, 991).— Ne lines by an interferometric method, and the density Full data arid analyses are given for the extreme of the dispersion electrons. The results agree with ultra-violet spectra due to a new type of violent the theory of Weisskopf and Wigner. A. J. M. condensed discharge through air at low pressure in Dependence of the intensity of the visible Ne a quartz capillary. N. M. B. lines of the positive column on the current strength. W. S c h ü t z (Ann. Physik, 1933, [v], 18, Analysis of the N9‘ bands. A. E. P a r k e r (Physical Rev., 1933, [ii], 44, 914—918).—Rotational 746—754).—Photographs of the Ne spectrum were analyses for the (4, 7), (5, 8), (6, 9), and (7, 10) bands, taken so that the product of time of exposure and perturbation data for the (5, 8) band, and additional current strength was const. The lines of a group lines in the (5, 8) and (13, 15) bands are tabulated. (p/c—Si) with a common initial term were not of const, N. M. B.- intensity under these conditions. A. J. M. Combination relations in the absorption spec­ Line absorption of sodium vapour for the two trum of liquid oxygen. J. W. E l l is and H. O. .»-lines. W. Z e h d e n (Z. Physik, 1933, 8 6 , 555— K n e s e r (Z. Physik, 1933, 8 6 , 583—592)—The 582).—Line absorption was measured with an absorption spectrum was investigated between 340 accuracy of 4% for the pressure range 1 X 10 6 to k 123 1 2 4 BRITISH CHEMICAL ABSTRACTS.----A. 4 x l 0-5 mm., and the results are compared with strong /-uncoupling in the 2n state on the Zeeman those of magnetorotation. A. B. D. C. patterns of the lines of the 2I1 ---->- 2£ CaH band at A. Energy balance, electron temperature, and 7000 is discussed. N. 51. B. voltage gradient in the positive column in mix­ Probe measurements for luminous arcs in air tures of Na vapour with Ne, He, and A. M. J. at atmospheric pressure. J. L. M y e r (Z. Physik, D r u y v e s t e y n and N. W a r m o ltz (Phil. Mag., 1934, 1933, 87, 1—18).—Potential drop in different regions [vii], 17, 1—27; cf. A., 1933, 1).—Either in pure Na of the arc was investigated using Fe, Cu, C, Ni, and vapour, or in Na-fa few mm. of Ne, He, or A, the Zn as electrodes. The cathode fall corresponds with power input in the discharge equals the output the second ionisation potential of the cathode and is (radiation+ wall energy). Discrepancies occur at little affected by the anode material; the anode fall higher pressures of the rare gas. H. J. E. was similarly investigated and gave results agreeing Nuclear spin and magnetic moment of sodium with those of Nottingham (J. Franklin Inst., 1928,. 206, 43). A. B. D. C. from hyperfine structure. L. P. G r a n a t h and C. M. V a n A t t a (Physical Rev., 1933, [ii], 44, 935— Standard copper wave-lengths in the region 942).—The observed hyperfine structure of the Na 100— 450 A. P. G. K r u g e r and F. S. C o o p e r D lines showed component separations : D2 (X 5890), (Physical Rev., 1933, [ii], 44, S26—S30).-—Intensities 0-0555, D x (X 5896), 0-0612 cm.-1 Relative intensity and 476 standard wave-lengths are tabulated. measurements indicate a nuclear spin of 3/2. The Possible errors are discusscd. N. M . B. calc, nuclear magnetic moment is 2-7/1840 Bohr Zeeman separation of infra-red krypton i lines. magneton. N. M. B. B. P o g a n y (Z. P hj^sik, 1933, 8 6 , 729— 737).— Transport of matter in arcs and flames. (7-Coupling is worked out (cf. A., 1933, 1219). Optical determination of the radii of alkali A. B. D. C. atom s. L. A. Ginsel (Arch. Neerland., 1933, [iiik], Absorption spectra due to excitation of inner 14, 285—333).—The intensity variation of spectral electrons. II. Mercury spectrum between lines due to the metal atom in an arc between the 1190 and 600 A. due to excitation of the (5 rf)10 metal and a G electrode was used to examine factors shell (Hglb). III. Cadmium spectrum from influencing the transport of metal. Line intensity 1100 to 600 A. due to excitation of the (4d)10 shell measurements were used to calculate the diffusion (Cdl*>). H. B e u t l e r (Z. Physik, 1933, 8 6 . 710— consts. of Na, Iv, Rb, and Cs in a Bunsen flame, 728;87,19—27). A. B . D. C. and their at. radii. H. J. E. Line shape as a function of the m ode of spectro­ Remarkable optical properties of the alkali graph slit irradiation. D. C. S t o c k b a r g e r and L. metals. C. Z e n e r (Nature, 1933, 132, 968).— B u r n s (J . Opt. Soc. Amcr., 1933, 23, 379— 3S5).— Treating electrons as moving in no field, Wood’s Non-coherent, coherent,I ens, and broad source modes observations (A., 1933, 1096) on the transparency of slit irradiation have been studied and the line shape of the alkali metals in ultra-violet light can be and its effect on resolution have been investigated for qualitatively accounted for; approx.
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