A theoretical revisit to the lowest ionization potentials in metal-metal bonds
1Department of Biological Science and Technology, National Chiao Tung University, No. 75, Po-Ai Street, Hsinchu City 300, Taiwan.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|June 22, 2012
Abstract:
The ties that bind: The electrostatic potential of quadruply bonded W(2)(hpp)(4) and its cation support the idea that the very low ionization energies are due to excitations from the metal-metal bonding core. Theoretical MRCI computations based on CASSCF orbitals show that the relativistic effect influences the lowest four ionization energies, leading to distinct IE sequences: IE(δ) < IE(π) < IE(σ) in W(2)(hpp)(4), and IE(δ) < IE(σ) < IE(π) in Mo(2)(hpp)(4).
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