• K V S R Apparao

Articles written in Proceedings – Section A

• A new band system of CuBr molecule

A new system of red degraded bands in the 3700–4000 Å region has been obtained in the spectrum of the CuBr molecule excited in an electrodeless discharge tube by a microwave oscillator. The band heads of this system are given by the formula:$$\begin{gathered} v ^{63} Cu ^{79} Br = 25538 \cdot 5 + 281 \cdot 9 \left( {\upsilon ' + \tfrac{1}{2}} \right) - 1 \cdot 35 \left( {\upsilon ' + \tfrac{1}{2}} \right)^2 - 314 \cdot 4 \hfill \\ \left( {\upsilon '' + \tfrac{1}{2}} \right) + 0 \cdot 86 \left( {\upsilon '' + \tfrac{1}{2}} \right)^2 \hfill \\ \end{gathered}$$. It has been found that the lower electronic state of this system is the same as the common lower state of the three known band systems, which is also the ground state of the molecule.

Some new bands recorded in the B and C systems are assigned vibrational quantum numbers.

• Isotope shift studies of the B3Σ−X3Σ bands of SO

The B3Σ−X3Σ bands of SO were excited in an electrodeless microwave (2450 Mc/s) discharge through trace amounts of sulphur enriched with 37% of34S and oxygen enriched with about 40% of18O. The emission spectra of32S16O,34S16O and32S18O were photographed on a Jarrell-Ash 3·4 m. grating spectrograph at a dispersion of 5 Å/mm. Isotope shift data obtained from the present studies support the revision of the earlier vibrational scheme (Henri and Wolff, 1929; Martin, 1932) by increasingv″-quantum numbering by two units as suggested by Norrish and Oldershaw (1959).

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