Submillimeter spectroscopy of H$_2$C$^{17}$O and a revisit of the   rotational spectra of H$_2$C$^{18}$O and H$_2$C$^{16}$O
  The rotational spectrum of the formaldehyde isotopologue H$_2$C$^{17}$O was investigated between 0.56 and 1.50 THz using a sample of natural isotopic composition. In addition, transition frequencies were determined for H$_2$C$^{18}$O and H$_2$C$^{16}$O between 1.37 and 1.50 THz. The data were combined with critically evaluated literature data to derive improved sets of spectroscopic parameters which include $^{17}$O or H nuclear hyperfine structure parameters. 
Holger S. P. M\"uller, Frank Lewen
astro-ph.GA astro-ph.IM astro-ph.SR physics.chem-ph