			15min:

LASER VAPORIZED SPECTRA OF A NEW RED SYSTEM OF SiN.

K. S. OJHA AND R. GOPAL, Laser and Spectroscopy Laboratory, Department of Physics, University of Allahabad, ALLAHABAD - 211002, INDIA .

The spectrum has been recorded for first time in the region 575 - 940 nm along with known blue-green systems using second harmonic of pulsed Nd: YAG laser for vaporization of rotating SiN target inside the ablation chamber and computer controlled Spex TRIAX 320 m monochromator fitted with TE cooled ICCD as a detector.

It consists of 50 new bands assigned to Delta v = 0, \pm 1, \pm 2, -3, -4 and -5 sequences a new band system with (0,0) band lying at 787 nm. The lower state vibrational constants are same as that of A² state reported by earlier workers. The vibrational constants of upper excited state are as follows:

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