THE $\tilde{B}^{2}\Sigma^{+}_{u} - \tilde{X}^{2}\Pi_{g}$ SYSTEM OF SiNSi: INVESTIGATION OF ROVIBRONIC STRUCTURE AND RENNER-TELLER INTERACTION BY LASER INDUCED FLUORESCENCE SPECTROSCOPY.

$^{a}$On leave from: Institute of Physics, University of Rzeszow, 35-310 Rzeszow, Poland, $^{b}$On leave from: Spectroscopy Division, Bhabha Atomic Research Centre, Mumbai, Maharastra 400 085 IndiaAuthor Institution: Steacie Institute for Molecular Sciences, National Research CouncilThe free SiNSi radical has been investigated in a molecular free jet by laser induced fluorescence excitation and dispersed fluorescence spectroscopy. The radicals have been generated by laser ablation of Si in the presence of $NH_{3}$ diluted (5%) in He. Excitation spectra of the $\tilde{B}^{2}\Sigma^{+}_{u} - \tilde{X}^{2}\Pi_{g}$ system have been recorded in the $32600 - 36400 cm^{-1}$ range. For most of the excitation bands, dispersed fluorescence spectra have been obtained. Very large Renner-Teller interaction has been observed in both electronic states. The excitation and dispersed fluorescence spectra have been vibrationally and rotationally analyzed. Rotational, vibrational, and Renner-Teller parameters will be presented