One-Electron Properties of Near-Hartree–Fock Wavefunctions. II. HCHO, CO

Abstract

The results of Hartree–Fock level self‐consistent‐field molecular orbital calculations using contracted Gaussian basis sets are reported for the ground states of the formaldehyde and carbon monoxide molecules. The best computed wavefunctions are shown to have total energies, at most, 0.05 a.u. from their Hartree–Fock limits. A large number of one‐electron properties were computed from the wavefunctions. Results for the carbon monoxide molecule are in excellent agreement with the Slater basis Hartree–Fock results of Huo [J. Chem. Phys. 43, 624 (1965)]. For formaldehyde the calculated molecular properties are in good agreement with experiment. Our best estimates for several of the properties in HCHO are: dipole moment, ${\mu }_z\text{\hspace{0.17em}=\hspace{0.17em}2.82}$ D; quadrupole moment, ${\theta }_{\mathrm{aa}}{\text{\hspace{0.17em}=\hspace{0.17em}0.0056\hspace{0.17em}×\hspace{0.17em}10}}^{\text{−26}}$ esu·cm², ${\theta }_{\mathrm{bb}}{\text{\hspace{0.17em}=\hspace{0.17em}0.250\hspace{0.17em}×\hspace{0.17em}10}}^{\text{−26}}{\mathrm{esu·cm}}^2$ , ${\theta }_{\mathrm{cc}}{\text{\hspace{0.17em}=\hspace{0.17em}−\hspace{0.17em}0.256\hspace{0.17em}×\hspace{0.17em}10}}^{\text{−26}}{\mathrm{esu·cm}}^2$ ; diamagnetic shielding at the proton, ${\sigma }_{\mathrm{aa}}^d\mathrm{(H)}\text{\hspace{0.17em}=\hspace{0.17em}92.63}\mathrm{ppm}{\mathrm{,\; \sigma }}_{\mathrm{bb}}^d\mathrm{(H)}\text{\hspace{0.17em}=\hspace{0.17em}94.68}\mathrm{ppm}{\mathrm{,\; \sigma }}_{\mathrm{ab}}^d\mathrm{(H)}\text{\hspace{0.17em}=\hspace{0.17em}52.80}\mathrm{ppm}{\mathrm{,\; \sigma }}_{\mathrm{cc}}^d\mathrm{(H)}\text{\hspace{0.17em}=\hspace{0.17em}147.13}\mathrm{ppm}$ , and ${\sigma }_{\mathrm{Av}}^d\mathrm{(H)}\text{\hspace{0.17em}=\hspace{0.17em}111.48}\mathrm{ppm}$ ; diamagnetic shielding at ¹³C, ${\sigma }_{\mathrm{aa}}^d\mathrm{(C)}\text{\hspace{0.17em}=\hspace{0.17em}288.50}\mathrm{ppm}{\mathrm{,\; \sigma }}_{\mathrm{bb}}^d\mathrm{(C)}\text{\hspace{0.17em}=\hspace{0.17em}355.34}\mathrm{ppm}{\mathrm{,\; \sigma }}_{\mathrm{cc}}^d\mathrm{(C)}\text{\hspace{0.17em}=\hspace{0.17em}371.60}\mathrm{ppm}$ , and ${\sigma }_{\mathrm{Av}}^d\mathrm{(C)}\text{\hspace{0.17em}=\hspace{0.17em}338.48}\mathrm{ppm}$ , diamagnetic susceptibilities, ${\chi }_{\mathrm{aa}}^d{\text{\hspace{0.17em}=\hspace{0.17em}−\hspace{0.17em}27.99, χ}}_{\mathrm{bb}}^d{\text{\hspace{0.17em}=\hspace{0.17em}−\hspace{0.17em}54.19, χ}}_{\mathrm{cc}}^d\text{\hspace{0.17em}=\hspace{0.17em}−\hspace{0.17em}61.53}$ , and ${\chi }_{\mathrm{Av}}^d\text{\hspace{0.17em}=\hspace{0.17em}−\hspace{0.17em}47.91}\mathrm{emu}/\mathrm{mole}$ ; deuteron quadrupole coupling constants, ${\mathrm{(eqQ/h)}}_{\mathrm{AA}}\text{\hspace{0.17em}=\hspace{0.17em}172.4}\mathrm{kc}/\sec {\mathrm{,\; (eqQ/h)}}_{\mathrm{BB}}\text{\hspace{0.17em}=\hspace{0.17em}−\hspace{0.17em}87.22}\mathrm{kc}/\sec$ , and ${\mathrm{(eqQ/h)}}_{\mathrm{CC}}\text{\hspace{0.17em}=\hspace{0.17em}−\hspace{0.17em}85.21}\mathrm{kc}/\sec {;}^{17}O\mathrm{quadrupole\; coupling\; constants}{\mathrm{,\; (eqQ/h)}}_{\mathrm{aa}}\text{\hspace{0.17em}=\hspace{0.17em}−\hspace{0.17em}2.28}\mathrm{Mc}/\sec {\mathrm{,\; (eqQ/h)}}_{\mathrm{bb}}\text{\hspace{0.17em}=\hspace{0.17em}12.8}\mathrm{Mc}/\sec ,\mathrm{and}{\mathrm{(eqQ/h)}}_{\mathrm{cc}}\text{\hspace{0.17em}=\hspace{0.17em}−10.5}\mathrm{Mc}/\sec$ .