The Equilibrium Geometry and Some Spectroscopic Constants of H2C4, a Molecule of Interest to Astrochemistry

✍ Scribed by M. Oswald; P. Botschwina

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 193 KB
• Volume: 169
• Category: Article
• ISSN: 0022-2852
• DOI: 10.1006/jmsp.1995.1013

✦ Synopsis

Using a large basis set of 220 contracted Gaussian-type orbitals and the coupled cluster single-, double-, and perturbative triple-excitation ( (\operatorname{CSD}(\mathrm{T})) ) method, the equilibrium geometry of the astrochemically important molecule (\mathrm{H}{2} \mathrm{C}{4}) is determined to be (r_{\mathrm{c}}(\mathrm{CH})=1.0806 \AA, \alpha_{\mathrm{e}}(\mathrm{HCH})=) (119.49^{\circ}, R_{1 \mathrm{e}}\left(\mathrm{C}{(1)} \mathrm{C}{(2)}\right)=1.3062 \AA, R_{2 \mathrm{e}}\left(\mathrm{C}{(2)} \mathrm{C}{(3)}\right)=1.2902 \AA), and (R_{3 \mathrm{e}}\left(\mathrm{C}{(3)} \mathrm{C}{(4)}\right)=1.2866 \AA). The equilibrium dipole moment amounts to (\mu_{\mathrm{e}}=-4.457 \mathrm{D}), and the equilibrium isomerization energy with respect to diacetylene is (194 \mathrm{~kJ} \mathrm{~mol}^{-1}). (C) 1995 Academic Press. Inc.