title: Remarks on catalytic reduction of CO2, H+ and H2 by monovalent Ni.
abstract: Prompted by catalysis of CO2 electroreduction by a tetraazamacrocyclic Ni(i)(cyclam) complex (cyclam = 1,4,8,11-tetraazacyclotetradecane), we examine theoretically the possibility of H2 reduction by this molecule. We show that the process 2 Ni(i) + H2 --> 2 [Ni(ii)(H-)] is thermodynamically facile, and that H2 could be reduced by a binuclear Ni(i) complex in two concerted 1e- processes. Our calculations also indicate that hydride complexes of Ni(iii)(cyclam) are significantly unstable thermodynamically and therefore they are unlikely to serve as intermediates in process of H2 evolution from water.
authors.affiliation: Interdisciplinary Center for Mathematical and Computational Modeling, University of Warsaw, Pawińskiego 5a, 02106 Warsaw, Poland. wg22@cornell.edu
authors.forename: Wojciech
authors.initials: W
authors.lastname: Grochala