Knowledge Bank

The rotational spectrum of the $ArN2O$ complex has been observed by molecular beam electric resonance techniques. The structure derived from this spectrum is consistent with those obtained for the isovalent species $ArCO2$ and $ArOCS$; i.e., it is a nearly prolate too (roughly T-shaped) with an argon-central-nitroqen bond distance of $3.45${\AA}. The measured dipole moment components are $\mu a=.043D$ and $\mu b=.149D$. The work on ArOCS has been extended to permit the determination of the first order centrifugal distortion constants from which are derived the harmonic force constants for the van der Waals modes. These are .0218 mdyn/{\AA} for the stretch and .0118 mdyn. {\AA} for the bend. The corresponding numbers for $ArCO2$ are .0174 mdyn/{\AA} and .0083 mdvn {\AA}. The structural and dynamical properties of the three molecule will be discussed and compared.