10min:

EMI Y. OKABAYASHI, TOSHIAKI OKABAYASHI AND MITSUTOSHI TANIMOTO, Department of Chemistry, Faculty of Science, Shizuoka University, Oya 836, Shizuoka.

The rotational spectrum of platinum monocyanide, PtCN, was observed by employing a source-modulation microwave spectrometer. The PtCN species was generated in a dc glow discharge through the mixture of CH₃CN and Ar by a sputtering reaction with a platinum sheet on a cathode. Paramagnetic lines were observed every 6GHz and assigned to three isotopomers, ¹⁹⁴PtCN, ¹⁹⁵PtCN, and ¹⁹⁶PtCN. There was no -type doubling, but hyperfine splitting due to ¹⁹⁵Pt nucleous for ¹⁹⁵PtCN. The hyperfine structure could be fitted to either ² _3/2 or ² _5/2 case(c) Hamiltonian within experimental error.

%From analysis of the huperfine strucuture, the ground states was found to be =3/2

The nuclear - spin interaction constant C_I was derived to be around 0.2 MHz, which was one order of magnitude larger than that of ¹⁹⁵PtCO (C_I = 0.0242 MHz). This result implies that low-lying electronic states would exist comparatively near to the ground electronic state, as in the case of NiCN.