Engineering topics
Publications and source records attributed to Durig, J. R..
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The vibrational spectra from 4000 to 33 cm-1 of several modecules which may be present in the atmosphere of the Jovian planets are studied 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 are produced photochemically from methane, ammonia, and hydrogen sulfide which are thought to be constituents of the planets with reducing atmospheres. Some of the compounds 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.
The Raman spectra of gaseous ethanol and ethanethiol have been investigated. Thiol torsional fundamentals for the gauche conformer of EtSH and EtSD have been observed and the asymmetric potential function for this vibration has been calculated. Methyl torsional transitions and overtones have also been observed for both of these molecules. Barriers to internal rotation for the methyl top are calculated to be 3.77 and 3.84 kcal/mol for the EtSH and EtSD compounds, respectively. Hydroxyl torsional fundamentals were observed at 207 and 170 per cm in the EtOH and EtOD spectra, respectively. Overtones of the methyl torsion in both molecules yield a barrier to internal rotation of 3.62 kcal/mol for the gauche conformer.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The vibrational spectra of (CH3)2PH and (CD3)2PH have been studied and assignments made. In the infrared, the region between 4000 and 33 wavelength/cm was recorded for the gaseous and solid states, while Raman spectra from 3500 to 10 wavelength/cm in the gaseous, liquid and solid states were observed. There is some evidence of weak hydrogen bonding, based on the behavior of the phosphorus-hydrogen stretching and bending modes. There also appears to be considerable interaction between the methyl rocking and phosphorus-carbon stretching modes. The a double prime and a prime torsional modes appear to be accidentally degenerate at 182 and 142 wavelength/cm for the 'light' and 'heavy' compounds, respectively. This gives barriers of 2.14 and 2.30 kcal/mole, respectively.
Explore the source record for details and available documents.
Infrared and Raman spectra have been obtained for biphosphine and biphosphine-d4 in both solid and vapor phases. From the spectral data, it is concluded that only one conformer exists in both solid and fluid phases and that this is the gauche conformer. A normal-coordinate analysis has also been performed, in which the 24 vibrational frequencies of the two isotopes have been fitted by 10 force constants to an overall average error of 1.0%. The PED indicates that there is practically no mixing of the normal modes in the P2H4 molecule but the P-P stretch and the PD2 wagging modes are extensively mixed for the P2D4 molecule.
Microwave spectra from 12.4 to 40.0 GHz were recorded for five isotopic species of 1,1-difluoroallene. A-type transitions were observed and R-branch assignments were made for the ground state and two vibrationally excited states. Several structural parameters of the compounds were determined. The dipole moment value obtained from Stark splitting was 2.07 plus or minus 0.03 D. A Coriolis coupling was observed between the two-low-frequency C = C = C bending modes.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The Raman spectrum of gaseous N2F4 at a pressure of 760 Torr was recorded with a spectral slit width of 3 kaysers. Ten of the expected eleven fundamentals of the symmetric motions of both the gauche and trans isomers give rise to strongly polarized Raman lines. These new data require a reassignment of some of the fundamentals for both the C2 and C2h conformers. The Raman of the solid at 18 K was also recorded. Both conformers were found in the solid even after annealing the sample for 9 hr at a temperature of 101.6 K and 3 hr at a temperature of 106.8 K. Bands attributable to the gauche isomer became more intense relative to those for the trans isomer after several hours of annealing.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.