The laboratory millimeter-wave spectrum of methyl formate in its ground torsional E state

The Laboratory Millimeter-wave Spectrum of Methyl Formate in Its Ground Torsional E State

Over 250 rotational transitions of the internal rotor methyl formate (HCOOCH3 ) in its ground ( V1 = 0) degenerate (E) torsional substate have been measured in the millimeter-wave spectral region. These data and a number of E-state lines identified by several other workers have been analyzed using an extension of the classical principal-axis method in the high barrier limit. The resulting rotat...

The Millimeter/sub-millimeter Spectrum of the Lis Radical in Its P I Ground State

The pure rotational spectrum of LiS …X 2 P i † has been recorded in the v ˆ 0 and v ˆ 1 states in the region 130±540 GHz using millimeter/sub-millimeter direct absorption methods. This radical was synthesized from lithium vapor and CS 2 in a DC discharge. Transitions arising from the two orbit components were measured, both which exhibited lambda-doubling and, for the X ˆ 1=2 ladder, hyper®ne i...

Ab Initio Study of the Rotational-torsional Spectrum of Methyl Formate

The molecular structure of methyl formate is determined from ab initio calculations. The molecule presents two conformers (cis and trans) with a 5.3 kcal mol 1 difference in energy. In the most stable cis conformer, the carbonyl group eclipses the methyl group. The internal rotation barriers are V3(cis) 1⁄4 368 cm 1 and V3(trans) 1⁄4 26 cm 1 for the methyl group and V CO 1⁄4 4826 cm 1 for the C...

The Rotational-torsional Spectrum of Methyl Formate:precise Measurements on and In- Terpretation of Millimetric Wave Transitions

Millimeter-Wave Spectrum of the NO Dimer

The pure rotational spectrum of the NO dimer, (14N16O)2, has been studied in the 225-400 GHz millimeter-wave region by means of direct absorption in a supersonic jet expansion. Previously, only 4 rotational transitions of (NO)2 had been measured in the microwave region. To these, we have added 66 new millimeter-wave transitions with values of J ranging from 4 to 16 and of Ka from 2 to 7. Most t...