Roland W. Lovejoy

The infrared spectrum of the ν1 and ν4 bands of 28SiH3D

Abstract The spectrum of the ν 1 and ν 4 SiH stretching bands of 28 SiH 3 D have been recorded and analyzed. The degenerate stretching mode is at 2188.504 cm −1 , only 1.103 cm −1 above the symmetric stretching mode. Several accidental and essential resonances affect these bands but all have been successfully analyzed by diagnolization of the secular determinant complete through the second order of the transformed Hamiltonian. One accidental resonance leads to a number of forbidden transitions through which a value of the rotational constant A 0 has been obtained.

The infrared spectrum of the ν1 band of SiD3H

Abstract High-resolution spectra of the ν 1 stretching band of SiD 3 H were recorded and analyzed, yielding values for ground- and upper-state constants and the band center. For 28 SiD 3 H, B 0 = 1.777482(14) and ν 1 = 2187.2070(17) cm −1 . Similar analyses were performed on the less abundant species 29 SiD 3 H and 30 SiD 3 H.

High-resolution infrared spectrum of 28SiH3D from 1450 to 1710 cm−1

Abstract The ν 2 and 2 ν 6 infrared bands of 28 SiH 3 D have been recorded between 1450 and 1710 cm −1 with 0.005 cm −1 apodized spectral resolution using a Fourier transform spectrometer. Line assignments were made from J = 0 to 25 and K = 0 to 15 for the ν 2 band, from J = 0 to 20 and K = 0 to 13 for the 2 ν 6 0 band, and from J = 0 to 20 and K = 0 to 8 for the 2 ν 6 2 band. Very strong perturbations were observed in all three components of the triad system, including l -type interactions between 2 ν 6 0 and 2 ν 6 2 and Fermi interactions between ν 2 and 2 ν 6 . Observed transitions were fit using ground state constants, derived from ground state combination differences, and upper state energy levels, obtained by diagonalizing an energy matrix including Fermi resonance terms between v 2 = 1 and v 6 = 2. Molecular coefficients and their method of determination are reported.

Absolute line strengths of phosphine gas near 5 μm

Abstract Absolute line strengths and line positions for over 200 vibration-rotation transitions of PH 3 gas were measured at 295 K, using a tunable-diode laser spectrometer. The spectral range covered was from 2153.697 to 2210.566 cm −1 . Line strength measurements were reproducible to better than 5% on average, and the uncertainty in line positions was less than 0.002 cm −1 . Certain of the PH 3 lines were pressure-broadened with H 2 gas, and the pressure-broadening coefficients were determined.

Absolute line strengths of 74GeH4 near 5 μm

Abstract Line positions and absolute line strengths were measured for 23 Q -branch lines of the ν 3 fundamental of 74 GeH 4 at 295 K, using an infrared tunable diode laser spectrometer. The spectral range covered was from 2109.9658 to 2110.6218 cm −1 . The average standard deviation of the measured line positions was 0.0006 cm −1 and that of the line strengths was 3.4%. Vibrational transition dipoles were computed from the measured line strengths, which gave 1226 ± 172 cm −2 amagat −1 for the ν 3 integrated band intensity.

Pressure broadening coefficients of 14N16ON2 gas mixtures

Abstract Pressure broadening coefficients were determined for gaseous 14 N 16 ON 2 mixtures at 223, 248, and 294 K using very high-resolution infrared spectroscopy. Particular attention was given to R -branch vibration-rotation transitions of the Δ v = 1 ← 0 band of NO for J″ = 7 2 to J″ = 19 2 which absorb infrared radiation in the spectral range from 1890.71 to 1909.78 cm −1 . Absolute linestrengths of pure 14 N 16 O were measured at 294 K for most of the R -branch transitions from J″ = 1 2 to J″ = 19 2 and a vibrational band intensity of S ν = 117 ± 3 cm −2 atm −1 at 273 K was calculated. Gas temperatures and pressures used in this study were chosen to simulate conditions of the Earths stratosphere, where NO is one of the gases known to be present in trace amounts.

Rotational spectrum of sulfuryl bromide fluoride

Abstract The rotational spectra of SO279BrF and SO281BrF have been obtained between 18 and 40 GHz. Both molecules are near-prolate symmetric rotors with a and b-type dipole components. A least-squares fit of the observed moments of inertia obtained by correcting for the bromine quadrupole interaction yields r (SBr) = 2.155 ± 0.006 A and ∢ FSBr=100.6°±1.5° structural parameters when r (SO) = 1.407 A , r (SF) = 1.56 A , and ⦠ OSO=123.7° are assumed.

Intensity of the sulfur dioxide rotational spectrum

Abstract The integral band intensity of the pure rotational absorption of SO2 gas has been determined from far-i.r. spectra. From the curve of growth, the value at 298°K is found to be Sob = 35.2±1.5atm-1 -cm-2. The entire set of experimental data has been analyzed using an absorption band model. The derived intensity agrees with that obtained from the curve of growth to be better than 10%. This result should be of value in connection with atmospheric models of the planet Venus.

Anomalous water experiments with silica powders

Abstract Silica powders were exposed to water vapor in an attempt to produce “anomalous water” in quantity. Cyclic condensation and evaporation of water led, in one experiment, to a viscous high boiling liquid which dried to a glass having an infrared absorption spectrum and an X-ray diffraction pattern like the “anomalous water” in capillaries. Although no evidence was seen of Water II, the volatile decamer of H2O proposed by Deryagin, experiments continue to attempt isolation of that material. Salts formed in “anomalous water” are to be expected, for quartz surfaces are not as clean as formerly supposed, but normally have surface salts (usually of sodium) at a concentration of about 1015 ions/cm2. This is not enough salt per capillary to allow for liquid columns of salt solution with the observed “anomalous” properties. Either more salts are scavenged from nearby surfaces by capillaries to provide for such columns, or a substance such as Deryagins Water II must be present. The mere presence of some salt is not sufficient to disprove the presence of Water II.

Upper-state rotational constants for the ν4 band of chlorine nitrate

Abstract The upper-state rotational constants for ν 4 band of 35 ClONO 2 are A ′ = 0.40361(4), B ′ = 0.0923(4) and C ′ = 0.07532(4)cm -1 . These values were originally determined by modeling the band. A normal coordinate analysis was subsequently conducted as an independent check of these rotational constants.