ASSIGNMENT OF THE MM- AND SMM-WAVE ROTATIONAL SPECTRA OF RARE ISOTOPOLOGUES OF CYANAMIDE AND THE $r_m^{(1)}$ MOLECULAR GEOMETRY OF NH$_2$CN
Loading...
Date
2009
Journal Title
Journal ISSN
Volume Title
Publisher
Ohio State University
Abstract
The cyanamide molecule is one of the prototype systems for the study of the large--amplitude inversion motion at the nitrogen atom, and it is also a potential astrophysical species. The mm-wave, smm-wave, and the far infrared spectra of the parent and the two principal deuterated isotopic species are now known in considerable detail., {\bf 190}, 353-364 (1998).}$^,$$~OSU~International~Symposium~on~Molecular~Spectroscopy}, WK08, 2008.} \vspace{0.2cm} Presently we report an extended analysis of rotational transitions in the $0^+$ and $0^-$ inversion states for 7 rare isotopic species of cyanamide, measured in the 118-650 GHz frequency region on a deuterated sample with natural abundance of carbon and nitrogen. The spectra of five isotopologues: H$_2$N$^{13}$CN, HDN$^{13}$CN, D$_2$N$^{13}$CN, HD$^{15}$NCN, and HDNC$^{15}$N, have been assigned for the first time. For D$_2$$^{15}$NCN and D$_2$NC$^{15}$N the knowledge of the rotational spectrum has also been considerably improved relative to preceding work., 248-261 (1972).}$^,$, {\bf 114}, 257-273 (1985).} \vspace{0.2cm} The availability of spectroscopic constants for 12 different isotopic species allowed determination of the complete $r_m^{(1)}$ and $r_m^{(1{\rm L})}$ geometries, 102-119 (1999).} of cyanamide, providing direct experimental information on the pyramidal nature of the NH$_2$ group in cyanamide and on the nonlinearity of the NCN segment. The new experimental geometry is compared with results of $ab~initio$ calculations.
Description
G.~Moruzzi et al., {\it J.~Mol.~Spectrosc.Z.~Kisiel et al., {\it 63$^{rdJ.~K.~Tyler et al., $J.~Mol.~Spectrosc.$, {\bf 43R.~D.~Brown et al., {\it J.~Mol.~Spectrosc.J.~K.~G.~Watson et al., $J.~Mol.~Spectrosc.$, {\bf 196
Author Institution: Institute of Physics, Polish Academy of Sciences, Al. Lotnikow; 32/46, 02-668 Warszawa, Poland; Department of Physics, The Ohio State University, Columbus; OH 43210
Author Institution: Institute of Physics, Polish Academy of Sciences, Al. Lotnikow; 32/46, 02-668 Warszawa, Poland; Department of Physics, The Ohio State University, Columbus; OH 43210