Spin–spin coupling constants for water polymers and hydronium ion complexes with water

Abstract

Ab intio EOM-CCSD calculations have been performed to obtain ¹⁷O–¹⁷O, ¹⁷O–¹H, and ¹H–¹H coupling constants for small water clusters and complexes of OH₃ ⁺ with one, two, and three H₂O molecules. Coupling constants ^2hJ(O–O) are quite small in water clusters, but increase significantly in complexes of OH₃ ⁺ with H₂O, and correlate with O–O distances. Protonation leads to a significant increase in the absolute value of ¹J(O–H) and a decrease in ²J(H–H) for OH₃ ⁺ compared to H₂O. The variations in O–O, O–H, and H–H coupling constants are related to cluster size and structure for water clusters, and to the degree of hydration of OH₃ ⁺.

Keywords:

• water clusters
• hydronium ion
• complexes of {\rm OH}_{\rm 3}^{\rm +} with H₂O
• EOM-CCSD coupling constants

Acknowledgement

The authors are grateful to the Ohio Supercomputer Center for continuing support of this research.