The magnetic vibrational circular dichroism (MVCD) spectra of the E-symmetry, ${\nu }_4$ 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 ${\nu }_4$ 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.

• Received 8 January 1993

DOI:https://doi.org/10.1103/PhysRevLett.71.979