Abstract

The fundamental band of the quadrupole spectrum of hydrogen has been observed. The frequencies of the Q(1), S(0), S(1), S(2), and S(3) lines have all been measured employing a maximum path of 1.4-km atm. The lines are of essentially Doppler width even at pressures as high as 10 atm. Using the ground state constants determined by Stoicheff from Raman measurements the molecular constants for the v=1 state have been determined and compared with the constants for higher vibrational states. The ratio of the intensity of the S(0) line to the intensity of the R(0) line of the HCl fundamental band has been determined. This ratio is compared with the theoretical prediction of James and Coolidge. In addition new theoretical ratios have been determined based on higher-order approximations of Kolos and Roothaan. These new calculations indicate that the 1–0, 2–0, and 3–0 bands should have relative intensities of 1:0.20:0.028, a result probably in agreement with the experimental observations of both the present work and the photographic infrared work of Herzberg. The induced dipole spectrum also has been observed. The absorption coefficients obtained agree with the results observed in the high-pressure experiments of Welsh and his co-workers. The Q_P, Q_R splitting is apparent even at only a few atmospheres pressure producing a relatively sharp (2 cm⁻¹ wide) transmission band centered on the position of Q(1).

© 1962 Optical Society of America

Calculations of Collision Narrowing of the Quadrupole Lines in Molecular Hydrogen

Thomas C. James
J. Opt. Soc. Am. 59(12) 1602-1606 (1969)

Quadrupole Spectrum of Molecular Hydrogen*

D. H. Rank and T. A. Wiggins
J. Opt. Soc. Am. 53(6) 759-760 (1963)

Infrared Spectrum of Hydrogen Fluoride: Line Positions and Line Shapes. Part II. Treatment of Data and Results*

W. F. Herget, W. E. Deeds, N. M. Gailar, R. J. Lovell, and A. H. Nielsen
J. Opt. Soc. Am. 52(10) 1113-1119 (1962)

Infrared Spectrum of Dideuteroacetylene (C₂D₂)

Eugene D. Tidwell and Earle K. Plyler
J. Opt. Soc. Am. 52(6) 656-664 (1962)

Rotational and Vibrational Constants of the HCl³⁵ and DCl³⁵ Molecules*

D. H. Rank, D. P. Eastman, B. S. Rao, and T. A. Wiggins
J. Opt. Soc. Am. 52(1) 1-7 (1962)