Electron Detachment and Subsequent Structural Changes of Water Clusters

Abstract

A cost-effective equation of motion coupled cluster method, EOMIP-CCSD(2), is used to investigate vertical and adiabatic ionization potential as well as ionization-induced structural changes of water clusters and compared with CCSD(T), CASPT2, and MP2 methods. The moderate N(5) scaling and low storage requirement yields EOMIP-CCSD(2) calculation feasible even for reasonably large molecules and clusters with accuracy comparable to CCSD(T) method at much cheaper computational cost. Our calculations shed light on the authenticity of EOMIP-CCSD(2) results and establish a reliable method to study of ionization energy of molecular clusters. We have further investigated the performance of several classes of DFT functionals for ionization energies of water clusters to benchmark the results and to get a reliable functionals for the same.

Reactivity of hydrogen-bonded complexes of water, methanol, phenol and methyl amine

“…A decrease in ionization potentials and an increase in electron affinity with an increase in the degree of water association were noted in the several works. [49][50][51] The increase in acid-base and donor-acceptor properties upon passing from the water monomer to its associates gave grounds to assume that the water associates should be more reactive in chemical reactions than the water monomer. A number of data are consistent with this assumption.…”