Off axis integrated cavity output spectroscopy of deuterated water isotopologues in 7178–7196 cm−1 spectral region

Abstract

Water is one of the most abundant molecules on the earth and its isotopic composition measurements find application in various fields. Even though it is an extensively studied molecule, many absorption lines of its isotopologues are still unknown. In the recent years, a significantly improved sensitivity of spectroscopic methods has brought forth a scope of studying the weak and extremely challenging molecular transitions. The paper describes an off axis integrated cavity output spectroscopic investigation the deuterated water isotopologues, viz. HD16O, HD17O and HD18O, in the 7178–7196 cm−1 spectral region. A few new ro-vibrational transitions of HD18O are reported along with their line strengths and assignments. Apart from this, observation of extremely weak transitions of deuterated water isotopologues and comparison with existing database and published data is also presented. The present study will find application in field of accurate and sensitive HD16O, HD17O and HD18O detections.