Search for {open_quotes}quadrupole-bound{close_quotes} anions. I.
- Physics Department, Virginia Commonwealth University, Richmond, Virginia 23284-2000 (United States)
- Quantum Theory Project, University of Florida, Post Office Box 118435, Gainesville, Florida 32611-8435 (United States)
In a classical model, some anions exist due to the attraction between an electron and a molecule{close_quote}s dipole moment. When the dipole moment is sufficiently large ({mu}{sub crit}{gt}2.5&hthinsp;D), an electron can be trapped. Can a sufficiently large quadrupole moment produce the same effect? To help answer this question, we can search for molecules with a large quadrupole moment and use predictive, {ital ab initio}, correlated quantum chemistry methods to assess whether an anion forms and, if it does, to discover its nature. For this purpose, coupled-cluster calculations are reported for the structure and properties of K{sub n}Cl{sub m} and K{sub n}Cl{sub m}{sup {minus}} (n,m=0{endash}2). The KCl{sub 2} superhalogen was found to have an electron affinity of 4.2 eV and is stable towards dissociation by 26 kcal/mol. The (KCl){sub 2} dimer has a rhombic ground state with a large electric quadrupole moment. Rhombic and linear configurations of the (KCl){sub 2}{sup {minus}} anion correspond to stationary states that are nearly degenerate in total energy. The rhombic anion has a single, weakly bound state that could be a {open_quotes}quadrupole-bound{close_quotes} state on the basis of a comparison of its characteristics with those of dipole-bound states. Linear KClKCl{sup {minus}} has seven excited states; four of them can be identified as dipole-bound states. KCl and KCl{sub 2} possess rather similar dipole moments and their anions have two excited dipole-bound states each. {copyright} {ital 1999 American Institute of Physics.}
- OSTI ID:
- 354509
- Journal Information:
- Journal of Chemical Physics, Vol. 111, Issue 2; Other Information: PBD: Jul 1999
- Country of Publication:
- United States
- Language:
- English
Similar Records
First experimental photoelectron spectra of superhalogens and their theoretical interpretations
Probing the coupling of a dipole-bound electron with a molecular core