Vibrational Zeeman effect for the nu 4 mode of haloforms (HCX3) determined by magnetic vibrational circular dichroism.

Abstract

The magnetic vibrational circular dichroism (MVCD) spectra of the E-symmetry, ${\ensuremath{\nu}}_{4}$ modes of ${\mathrm{HCCl}}_{3}$, ${\mathrm{HCBr}}_{3}$, ${\mathrm{HCI}}_{3}$, and ${\mathrm{DCCl}}_{3}$ are presented. In each case, an MVCD A term indicating a first order vibrational Zeeman effect is observed. The vibrational g values for the ${\ensuremath{\nu}}_{4}$ mode of these haloforms were determined for the first time by moment analysis of the MVCD and absorption spectra. A partially charged ``elastic bar'' model is proposed to qualitatively explain the observed MVCD A terms.