S. Paddi Reddy

The Band Spectra of NiCl and NiBr in the Visible

The emission spectra of NiCl and NiBr in the region λ3900-4800 A have been photographed under high dispersion. The spectrum of NiCl consists of nine separate brief systems of bands while the NiBr spectrum consists of six systems of bands. The observed bromine isotope effect in three of the band systems of the NiBr molecule confirms the vibrational analyses. Tables of vibrational constants of the different band systems of each molecule are presented.

New band systems of NiCl in the photographic infrared

High dispersion spectrograms of NiCl, in the photographic infrared (λ6350−λ8750Å) have shown the existence of five new band systems, designated as F, G, H, I and J. The bands in all the five systems are degraded to longer wavelengths. The F, G and I systems consist of single headed bands while H and J systems consist of double headed bands. Approximate vibrational constants have been determined from the vibrational analysis. The observed structure of the bands indicates doublet-doublet transitions, as in the visible band systems of NiCl.High dispersion spectrograms of NiCl, in the photographic infrared (λ6350−λ8750A) have shown the existence of five new band systems, designated as F, G, H, I and J. The bands in all the five systems are degraded to longer wavelengths. The F, G and I systems consist of single headed bands while H and J systems consist of double headed bands. Approximate vibrational constants have been determined from the vibrational analysis. The observed structure of the bands indicates doublet-doublet transitions, as in the visible band systems of NiCl.

The Complex Band System of MnF in the Near Ultra-violet

The complex band spectrum of MnF in the near ultra-violet has been photographed under high dispersion. A new analysis of the observed heads has been made, but the transition, in agreement with the earlier work of Bacher, is still interpreted as 7II-7Σ.

The spectrum of iron monochloride in the visible

Abstract The spectrum of FeCl excited both in high-frequency and heavy-current discharges, reveals the existence of four discrete band systems in the region λλ4690–6560. Extending Mullers designation of the two near ultraviolet systems of FeCl, these were designated as systems III, IV, V, and VI starting from the violet end. Of these, system III consists of four marked sequences of red degraded bands. The structure of this band system was observed to be complex. The strong Δv = 0 and +1 sequences were photographed using the second order of a 21-ft concave grating spectrograph. The observed structure of the bands was interpreted on the basis of a 4Πa,b-4Σ transition, the lower 4Σ state being common to system II of FeCl. The vibrational analyses of systems IV, V, and VI which consist of single-headed bands have also been carried out and the constants derived. Each of systems V and VI corresponds to transitions between two excited states of the FeCl molecule.