Local minima of ground hypersurfaces. The cases of He2+3 and of the BeH2+2 nonclassical dihydrogen complex

✍ Scribed by Petros Valtazanos; Cleanthes A. Nicolaides

• Book ID: 103026070
• Publisher: Elsevier Science
• Year: 1990
• Tongue: English
• Weight: 580 KB
• Volume: 172
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(90)85398-v

✦ Synopsis

We report the existence of special features in the bonding of the molecules He j+ and BeH:+ Their hypersurfaces have only local minima at 0.4 and 5.2 eV below the energies of (Hz+ 'Xl +He) and (BeH *+ ?E+ t H), respectively. In Czv symmetry the molecules are bound. Vibrational analysis reveals that symmetry breaking turns the He :' minimum into a saddle point, and thus the molecule fragments into 2He+ t He. By contrast, the Be@+ minimum is shown 10 hold up under symmetry breaking. Being the ground state, it can trap energy whose only escape is via multidimensional tunneling. The bonding characteristics of BeHi+ depict a structure of the type. Be"'+" . ..HZ_ The formation of this "dihydrogen complex" is due to the vacanl metal-ion orbitals, something which is verified by additional computations on BeH: . These results are compared with analogous bonding situations in transition-metal compounds.