caa a22 4500 605512752 CHVBK 20210128100657.0 cr unu---uuuuu 210128e20150401xx s 000 0 eng 10.1007/s00894-015-2638-9 doi (NATIONALLICENCE)springer-10.1007/s00894-015-2638-9 Microsolvation and hydration enthalpies of CaS2O3(H2O) n ( n  = 0-19) and S2O3 2−(H2O) n ( n  = 0-16): an ab initio study [Elektronische Daten] [Victor Rosas-García, Isabel del Carmen Sáenz-Tavera, María del Rosario Rojas-Unda] We studied microhydrated calcium thiosulfate and its ions at the restricted Hartree-Fock RHF/6-31G* level of theory. A semiempirical molecular dynamics search of progressively more hydrated species provided lowest-energy configurations that were then fully optimized and characterized as energy minima at the RHF/6-31G* level of theory. The first solvation shell of calcium thiosulfate contains 18 water molecules, while the first solvation shell of thiosulfate ion consists of 15 water molecules. QTAIM calculations show hydrogen bonding to sulfur. At 298.15K, we estimate the total standard enthalpies of hydration for thiosulfate ion and calcium thiosulfate at infinite dilution as −301kcalmol−1 and −335kcalmol−1, respectively. The dissociation of hydrated calcium thiosulfate at infinite dilution is predicted to be an endothermic process with an enthalpy of 262kcalmol−1. Based on some experimental data, the predominant form of calcium thiosulfate in solution is predicted to be the contact ion pair. Graphical Abstract Hydrated calcium thiosulfate, showing the first solvation shell Springer-Verlag Berlin Heidelberg, 2015 Ab initio nationallicence Calcium thiosulfate nationallicence Hydration enthalpy nationallicence Hydration shell nationallicence Thiosulfate ion nationallicence Rosas-García Victor Facultad de Ciencias Químicas, Universidad Autónoma de Nuevo León, UANL, Ave. Universidad S/N, Ciudad Universitaria, C. P. 66451, San Nicolás de los Garza, N. L., Mexico aut Sáenz-Tavera Isabel del Carmen Facultad de Ciencias Químicas, Universidad Autónoma de Nuevo León, UANL, Ave. Universidad S/N, Ciudad Universitaria, C. P. 66451, San Nicolás de los Garza, N. L., Mexico aut Rojas-Unda María del Rosario Facultad de Ciencias Químicas, Universidad Autónoma de Nuevo León, UANL, Ave. Universidad S/N, Ciudad Universitaria, C. P. 66451, San Nicolás de los Garza, N. L., Mexico aut Journal of Molecular Modeling Springer Berlin Heidelberg 21/4(2015-04-01), 1-9 1610-2940 21:4<1 2015 21 894 https://doi.org/10.1007/s00894-015-2638-9 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00894-015-2638-9 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Rosas-García Victor Facultad de Ciencias Químicas, Universidad Autónoma de Nuevo León, UANL, Ave. Universidad S/N, Ciudad Universitaria, C. P. 66451, San Nicolás de los Garza, N. L., Mexico aut NATIONALLICENCE 700 1- Sáenz-Tavera Isabel del Carmen Facultad de Ciencias Químicas, Universidad Autónoma de Nuevo León, UANL, Ave. Universidad S/N, Ciudad Universitaria, C. P. 66451, San Nicolás de los Garza, N. L., Mexico aut NATIONALLICENCE 700 1- Rojas-Unda María del Rosario Facultad de Ciencias Químicas, Universidad Autónoma de Nuevo León, UANL, Ave. Universidad S/N, Ciudad Universitaria, C. P. 66451, San Nicolás de los Garza, N. L., Mexico aut NATIONALLICENCE 773 0- Journal of Molecular Modeling Springer Berlin Heidelberg 21/4(2015-04-01), 1-9 1610-2940 21:4<1 2015 21 894