A Broadband Microwave Fourier Transform Spectrometer, Especially Designed for Stark Effect Investigations of Almost Nonpolar Molecules; the Electric Dipole Moment and the Anisotropy in the Static Electric Polarizability Tensor

A bridge type microwave Fourier transform spectrometer, equipped with flat oversized Stark cells and an operational range from 8 GHz to 40 GHz is described. As application we report the experimental determination of the vibronic ground state dipole moment and of the anisotropy in the static polarizability of 1,1-dideuteroallene. Our experimental values are: /za = 0.0053(2) D for the dipole moment, and (ay — a ± ) = 4.26(6) • 10~ 2 4 cm , for the polarizability anisotropy.