# GLOBAL FIT OF TUNNELING SPLITTINGS IN THE K=0 A-TYPE MICROWAVE SPECTRUM OF THE METHANOL DIMER

Please use this identifier to cite or link to this item: http://hdl.handle.net/1811/13015

Files Size Format View
1994-FC-06.jpg 127.9Kb JPEG image

 Title: GLOBAL FIT OF TUNNELING SPLITTINGS IN THE K=0 A-TYPE MICROWAVE SPECTRUM OF THE METHANOL DIMER Creators: Ohashi, N.; Hougen, Jon T. Issue Date: 1994 Publisher: Ohio State University Abstract: Theoretical results previously developed using an IAM-like multi-dimensional tunneling formalism are applied to tunneling splitting patterns recently measured at NIST and Kiel University for a type R(J) microwave transitions for various isotopomers of the methanol dimer. Permutation-inversion group $G_{36}$ species assignments for the 16 tunneling components of a give R(J) transition arising from 25 different tunneling motions are presented for $0 \leq J \leq 4$ for the normal isotopomer. Permutation-inversion group $G_{18}$ species assignments for the 10 tunneling component of a given R(J) transition arising from 13 different tunneling motions are presented for $0 \leq J \leq 3$ for the two mixed ${^{12}}C, \ {^{13}}C$ isotopomers. As a first stage of the analysis, a simplified two-top treatment of suitably averaged line frequencies is carried out in which only the (domainant) tunneling splitting arising from internal rotation of the two methyl tops of the dimer is considered. Relatively large top-top interaction terms must be included in this two-top treatment, which is surprising in view of the large distance between the two methyl rotors in the methanol dimer. As a second stage of the analysis, a tunneling treatment taking into account all tunneling splittings is carried out. Because only $K=0$ a-type transitions are available some ambiguity remains in the symmetry assignments and tunneling parameters reported in this work. Description: Author Institution: Department of Physics, Faculty of Science, Kanazawa University; Molecular Physics Division, National Institute of Standards and Technology URI: http://hdl.handle.net/1811/13015 Other Identifiers: 1994-FC-06