The predicted infrared spectrum of ZrO and its possible presence in S stars

Astrophysically useful radiative transition parameters for the e 1Π–X 1Σ+ and 1Σ+–X 1Σ+ systems of zirconium oxide

“…In Table 3, the v = 0 sequence bands except (0, 0) and (1, 1) bands are less intense. The (5, 5) band transition is found absent but Murthy (1980b) has predicted its wavelength and the reported value of the FC factor is 0.002. This transition bands are expected to lie in the 5319 to 6797 Å wavelength region, with the most intense band (0, 0) at 5860 Å.…”

“…The wavelength (λ v v ) and relative intensity (I v v ) of the respective band systems used in the present study have been collected from Murthy (1980b).…”

“…In the case of e 1 -X 1 and 1 + -X 1 + systems of 90 ZrO molecule, Murthy (1980aMurthy ( , 1980b has reported a partial array of FC factors using an approximate analytical method suggested by Fraser and Jarmain (1953). Hence we have evaluated the FC factors and r-centroids for all the experimentally observed vibrational levels using the molecular constants from Murthy (1980b) and Hammer and Davis (1981).…”

“…The e 1 -X 1 + (6495 Å) and 1 + -X 1 + (5860 Å) band systems have been identified in the spectra of the pure S-type star R Cyg by Wyckoff and Clegg (1978). The spectrum of the 90 ZrO molecule is of considerable astrophysical interest since it is one of the main absorption features in the spectra of S-type stars (Murthy 1980b). The absorption bands of ZrO have been observed in stars, particularly the class of objects denoted as S-type stars (Johnson 1982;Littleton and Davis 1985).…”

“…Hence we have evaluated the FC factors and r-centroids for all the experimentally observed vibrational levels using the molecular constants from Murthy (1980b) and Hammer and Davis (1981). FC factors are not only useful for intensity calculations but are also useful in studies of radiative transition in stellar and other astrophysical atmospheres which contain molecular species.…”