The Far Infrared Absorption Spectra of Ammonia and Phosphine Gases under High Resolving Power

摘要: A spectrometer of large aperture employing a reflection grating the echelette type ruled to concentrate radiation in region 1st order 90\ensuremath{\mu} has been applied spectral range from 60 125\ensuremath{\mu}. The resolving power was several times that hitherto obtained this region. pure rotation absorption spectra water vapor and gases N${\mathrm{H}}_{3}$ P${\mathrm{H}}_{3}$ have investigated. In case lines shown as single observations Badger Cartwright found under higher resolution present work be doublets with doublet separation 1.33 ${\mathrm{cm}}^{\ensuremath{-}1}$. Despite similarity structure molecules exhibit no trace doubling. frequencies mid-frequencies agree very accurately formulas ${{\ensuremath{\nu}}_{J}}^{J\ensuremath{-}1}=BJ\ensuremath{-}D{J}^{3}$. Determinations moments inertia $A$ made measurement led slight revision values for moment $C$ molecular dimensions by Dennison Uhlenbeck.