Magnetic Susceptibility Anisotropy, Molecular Quadrupole Moment, and the Sign of the Electric Dipole Moment in OCS

摘要

The molecular Zeeman effects of16O12C32S and16O12C34S have been observed under high resolution in magnetic fields up to 30 000 G. Conventional microwave spectroscopy is combined with a 6hyphen;ft long magnet to yield accurate firsthyphen; and secondhyphen;order magnetic field parameters. The magnetic susceptibility anisotropy of the OCS molecule iskhgr;perp;ndash;khgr;par;thinsp;equals;thinsp;lpar;9.27thinsp;plusmn;thinsp;0.10rpar;thinsp;times;thinsp;10minus;6ergsol;G2middot;mole. The moleculargvalues for the two isotopes obtained from theJthinsp;equals;thinsp;0thinsp;rarr;thinsp;Jthinsp;equals;thinsp;transitions aregperp;lpar;16O12C32Srpar;thinsp;equals;thinsp;minus;thinsp;0.028711thinsp;plusmn;thinsp;0.00004andgperp;lpar;16O12C34Srpar;thinsp;equals;thinsp;minus;thinsp;0.028127thinsp;plusmn;thinsp;0.00004. These data yield the sign of the molecular electric dipole moment which hasminus;OCSplus;polarity. Combiningkhgr;perp;ndash;khgr;par;andgperp;lpar;16O12C32Srpar;gives the molecular quadrupole moment ofQpar;lpar;16O12C32Srpar;thinsp;equals;thinsp;minus;thinsp;lpar;0.88thinsp;plusmn;thinsp;0.15rpar;thinsp;times;thinsp;10minus;26esumiddot;cm2.