The molecular structure of gaseous methyl vinyl ether at room temperature, studied by molecular orbital constrained electron diffraction and microwave spectroscopy

Abstract

The gas phase molecular structure of methyl vinyl ether at room temperature has been studied by joint analysis of electron diffraction and microwave data. Constraints on geometrical and thermal parameters were derived from the geometry and force field of the s-cis form, obtained by ab-initio calculations (4–21 G basis set) after complete geometry relaxation. A range of models was investigated that fits all available data (infrared, microwave and electron diffraction). The following rg/rα-parameters were obtained: CC: 1.337 Å, C(sp2)O: 1.359 Å, C(sp3)O: 1.427 Å, <CH> : 1.102 Å ∠CCO : 127.3° and ∠COC: 116.8°. Experimental rgre (ab initio) corrections are given for CC, C(sp2)O and Csp3)O.This investigation demonstrates that molecular orbital constrained electron diffraction is sufficiently reliable and in such a manner that it can be applied to more complicated problems.