Premium
O−H⋅⋅⋅O Interactions Involving Doubly Charged Anions: Charge Compression in Carbonate–Bicarbonate Crystals
Author(s) -
Braga Dario,
D'Oria Emiliana,
Grepioni Fabrizia,
Mota Fernando,
Novoa Juan J.,
Rovira Concepció
Publication year - 2002
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/1521-3765(20020301)8:5<1173::aid-chem1173>3.0.co;2-k
Subject(s) - ab initio , chemistry , ion , crystallography , crystal structure , bicarbonate , crystal (programming language) , acceptor , ab initio quantum chemistry methods , salt (chemistry) , carbonate , reactivity (psychology) , hydrogen bond , inorganic chemistry , molecule , physics , organic chemistry , computer science , programming language , condensed matter physics , medicine , alternative medicine , pathology
The O−H⋅⋅⋅O interaction formed by the anions HCO 3 − and CO 3 2− has been investigated on the basis of data retrieved from the Inorganic Crystal Structure Database (ICSD) and by means of ab initio computations. It has been shown that the O⋅⋅⋅O separations associated with HCO 3 − ⋅⋅⋅CO 3 2− interactions are shorter than those found in crystals containing hydrogen carbonate monoanions such as HCO 3 − ⋅⋅⋅HCO 3 − . Ab initio MP 2/6‐311G++(2d,2p) computations on the crystal Na 3 (HCO 3 )(CO 3 )⋅2 H 2 O have shown that the interaction between the monoanion donor and the dianion acceptor, for example HCO 3 − ⋅⋅⋅CO 3 2− , is more repulsive than that between singly charged ions, for example HCO 3 − ⋅⋅⋅HCO 3 − , but is largely overcompensated for by anion–cation electrostatic attractions. The shortening of the − O−H⋅⋅⋅O 2− interaction relative to the − O−H⋅⋅⋅O − interaction has been explained as a consequence of the increased charge compression , that is of the stronger cation–anion interactions established by the CO 3 2− dianions with respect to those established by monoanions, and does not reflect an increase in the strength of the − O−H⋅⋅⋅O n − interaction. To expand the structural sample in the crystal packing analysis, the structure of the novel mixed salt K 2 Na(HCO 3 )(CO 3 )⋅2 H 2 O has been determined by single‐crystal X‐ray diffraction and compared with the structure of the salt Na 3 (HCO 3 )(CO 3 )⋅2 H 2 O used in the computations.