The intermolecular interactions in the dimers of m-nisoldipine polymorphism were studied by B3LYP calculations and quantum theory of ＂atoms in molecules＂ （QTAIM） studies. Four geometries of dimers were obtained： ...The intermolecular interactions in the dimers of m-nisoldipine polymorphism were studied by B3LYP calculations and quantum theory of ＂atoms in molecules＂ （QTAIM） studies. Four geometries of dimers were obtained： dimer I （a：dimer, O…H--N）, dimer II （b-dimer, O…H--N）, dimer III （b-dimer, n-stacking-c）, and dimer IV （b-dimer, n-stacking-p）. The interaction energies of the four dimers are along the sequence of II〉I〉III〉IV. The intermolecular distance of the interactions follows the order： I （O…H--N）〈II （O…H--N）, and III （n-stacking）〈 IV （n-stacking）. Both the O…H--N hydrogen-bonding and n-stacking interactions belong to weak non-covalent interactions. The O…H--N hydrogen-bonding interactions with more electrostatic characters are stronger than the n-stacking interactions. The strength of the weak interactions decreases in the order： I〉II〉III〉IV, and the electrostatic character decreases along the sequence： I〉II〉III〉IV.展开更多
基金Project supported by the National Natural Science Foundation of China （Nos. 20801017, 20973053, 21073051）, the Natural Science Foundation of Hebei Province （Nos. B2010000371, B2011205058）, the Education Department Foundation of Hebei Province （No.ZD2010126）.
文摘The intermolecular interactions in the dimers of m-nisoldipine polymorphism were studied by B3LYP calculations and quantum theory of ＂atoms in molecules＂ （QTAIM） studies. Four geometries of dimers were obtained： dimer I （a：dimer, O…H--N）, dimer II （b-dimer, O…H--N）, dimer III （b-dimer, n-stacking-c）, and dimer IV （b-dimer, n-stacking-p）. The interaction energies of the four dimers are along the sequence of II〉I〉III〉IV. The intermolecular distance of the interactions follows the order： I （O…H--N）〈II （O…H--N）, and III （n-stacking）〈 IV （n-stacking）. Both the O…H--N hydrogen-bonding and n-stacking interactions belong to weak non-covalent interactions. The O…H--N hydrogen-bonding interactions with more electrostatic characters are stronger than the n-stacking interactions. The strength of the weak interactions decreases in the order： I〉II〉III〉IV, and the electrostatic character decreases along the sequence： I〉II〉III〉IV.
