The microwave torsional-rotational spectra of gauche CH 3 CD 2 OH and CH 3 CD 2 OD have been identified, assigned, and analyzed up to 70 GHz. From the observed a-and c-dipole transitions, it has been possible to determine the effective rotational coefficients and the gauche tunneling energy of the h
Parity-Violating Potentials for the Torsional Motion of Methanol (CH3OH) and Its Isotopomers (CD3OH, 13CH3OH, CH3OD, CH3OT, CHD2OH, and CHDTOH)
โ Scribed by Robert Berger; Martin Quack; Achim Sieben; Martin Willeke
- Publisher
- John Wiley and Sons
- Year
- 2003
- Tongue
- German
- Weight
- 182 KB
- Volume
- 86
- Category
- Article
- ISSN
- 0018-019X
No coin nor oath required. For personal study only.
โฆ Synopsis
Dedicated to Professor Duilio Arigoni on the occasion of his 75th birthday
We present calculations on the parity-conserving and the parity-violating potentials in several MeOH isotopomers for the torsional motion by the newly developed methods of electroweak quantum chemistry from our group. The absolute magnitudes of the parity-violating potentials for MeOH are small compared to H 2 O 2 and C 2 H 4 , but similar to C 2 H 6 , which is explained by the high (threefold) symmetry of the torsional top in MeOH and C 2 H 6 . -Chiralร and -achiralร isotopic substitutions in MeOH lead to small changes only, but vibrational averaging is discussed to be important in all these cases. Simple isotopic sum rules are derived to explain and predict the relationships between parity-violating potentials in various conformations and configurations of the several isotopomers investigated. The parity-violating energy difference D pv E E pv (R) ร E pv (S) between the enantiomers of chiral CHDTOH, first synthesized by Arigoni and co-workers, is for two conformers ca. ร 3.66 ยฅ 10 ร17 and for the third one 7.32 ยฅ 10 ร17 hc cm ร1 . Thus, for D pv E, the conformation is more important than the configuration (at the equilibrium geometries, without vibrational averaging). Averaging over torsional tunneling may lead to further cancellation and even smaller values.
๐ SIMILAR VOLUMES
We record double resonance spectra of the 4ฮฝ 1 band of jet-cooled 13 C-methanol using single rotational state selection in the ฮฝ 1 fundamental and subsequent promotion of the selected molecules to the fourth vibrational level. We then detect transitions to the final excited states by infrared laser
The rate constants for the reactions of OH radicals with CH 3 OCF 2 CF 3 , CH 3 OCF 2 CF 2 CF 3 , and CH 3 OCF(CF 3 ) 2 have been measured over the temperature range 250-430 K. Kinetic measurements have been carried out using the flash photolysis, laser photolysis, and discharge flow methods combine
Refractive indices were measured over the entire composition range at atmospheric pressure ลฝ . ลฝ for the binary mixtures CH OH with CH OCH CH OCH CH OCH 2,5,8,11,14 3 3 2 2 2 3 2 3 . ลฝ . ลฝ . pentaoxapentadecane, or Tegdme and CH OCH CH OCH CH OCH n s 3แ9 3 2 2 2n 2 3 ลฝ . Pegdme 250 at temperatures f
CF 3 CF 2 CH 2 OH is a new chlorofluorocarbon (CFC) alternative. However, there are few data about its atmospheric fate. The kinetics of its atmospheric oxidation, the OH radical reaction of CF 3 CF 2 CH 2 OH, has been investigated in a 2-liter Pyrex reactor in the temperature range of 298 ฯณ 356 K u
A new layered aluminophosphate [NH 3 CH 2 CH(OH)CH 3 ] 3 ' Al 3 P 4 O 16 containing a racemic mixture of isopropanolamine has been synthesized using isopropanolamine as the predominant solvent and the template and its structure was determined by means of single-crystal X-ray di4raction. The title co