Stark Effect and Dipole Moment of Methyl Fluoride

摘要

Highhyphen;precision Stark effect measurements have been made on theJ=1rarr;2 transition of methyl fluoride in the shorter millimeter wave region. A parallelhyphen;plate Stark cell employing silverhyphen;coated glass plates held apart by optically ground quartz spacers was employed. Millimeter wave power was fed between the plates by two sets of horns, one of which allowed for measurement of the Dgr;M=0 transitions and the other for measurement of the Dgr;M=plusmn;1 transitions. The dc voltage across the Stark plates was measured with a standard potentiometer. Both the firsthyphen; and secondhyphen;order effects were measured. The resulting value for the dipole moment of CH3F is mgr;=1.8555plusmn;0.0015 D for the ground vibrational state.