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Durig, J. R.

Publications and source records attributed to Durig, J. R..

At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS1976

Infrared spectra of molecules and materials of astrophysical interest

The vibrational spectra from 4,000 to 33/cm of several molecules which may be present in the atmosphere of the Jovian planets or exist in outer space were studied. These studies have been made to provide vibrational frequencies which can be used to: (1) determine the composition of the cloud covers of several of the planets, (2) provide structural information under favorable circumstances, (3) provide necessary data from which accurate thermodynamic data can be calculated, and (4) furnish information as to the nature of the potential energy function of the molecules and forces acting within them. Some of the molecules studied can be produced photochemically from methane, ammonia, and hydrogen sulfide which are thought to be constituents of the planets with reducing atmospheres. Some of the compounds will polymerize under ultraviolet radiation and drop out of the atmospheres. However, planets with a hot base, like that of Jupiter, may rebuild molecules destroyed photochemically. These criteria were used in selecting the compounds under study.

Durig, J. R.↗
NASA NTRS1976

Vibrational spectra and structure of dimethyl oxalate and dimethyl oxalate-d6

The vibrational spectra of dimethyl oxalate-d6 have been examined in connection with a re-examination of the spectra and structure of dimethyl oxalate. The vibrational spectra of the compound had previously been interpreted as being consistent with a trans C2h structure in the solid phase and a non-planar C2 form in the liquid and gas phases. This behavior is not consistent with that observed in similar compounds and a re-evaluation of the facts suggests that the major spectral changes which are observed may be caused by destroying an intermolecular association in going from the solid to the liquid phase, which allows the methyl groups to assume positions out of the plane. Some modifications and additions have been made in the vibrational assignment and assignments are presented for the deuterated compound.

Durig, J. R.↗
NASA NTRS1976

The Raman spectra of N-14O2 and N-15O2 solids at 20 K

The Raman spectra of N-14O2 and N-15O2 have been studied at 20 K. The far infrared of N-14O2 at 20 K was also measured. The data were assigned on the basis of a C-sub 2 nu molecular model. Normal coordinate calculations were performed for a variety of assignments. The assignment that yielded the best fit is presented. The solid state effects are discussed.

Durig, J. R.↗
NASA NTRS1975

Raman spectra of gases. XVIII - Internal rotational motions in ethylamine and ethylamine-d2

The Raman spectra of gaseous CH3CH2NH2 and CH3CH2ND2 have been recorded at wavenumbers from 100 to 600. Both ground and excited states of the methyl and amino torsional modes for the gauche conformer have been observed. The overtone of the methyl torsion has also been observed for the gauche conformer. The methyl barriers in the gauche conformers of the CH3CH2NH2 and CH3CH2ND2 molecules were found to be 3.71 + or - 0.05 and 3.59 + or - 0.05 kcal/mole, respectively. The apparent difference in the barrier heights for these two isotopic species is attributed to a difference in the coupling between the methyl and amino torsions in these two molecules. The potential function for internal rotation around the C-N bond in CH3CH2ND2 was determined. The energy difference between the potential energy minima of the gauche and trans conformations is 0.592 kcal/mole with the trans being the more stable.

Durig, J. R.↗
NASA NTRS1975

Torsional potential function of glyoxal

We have shown, using the fact that glyoxal exists in the trans conformer and the pseudo stable cis conformer that a potential function can be calculated which fits the infrared data of the trans conformer and the microwave intensity data of the cis conformer. This potential function was extended to the d sub 1 and d sub 2 analogs. A study of the potential function of 1,3-butadiene using a different molecular geometry than was previously used was undertaken. Results are presented with different possible vibrational assignments and potential functions which would be consistent with the observed infrared and Raman spectra.

Durig, J. R.↗