Jagoda-Cwiklik Barbara, Jungwirth Pavel, Rulísek Lubomír, Milko Petr, Roithová Jana, Lemaire Joël, Maitre Philippe, Ortega Jean Michel, Schröder Detlef
Institute of Organic Chemistry and Biochemistry, Center for Biomolecules and Complex Molecular Systems, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 16610 Prague 6, Czech Republic.
Chemphyschem. 2007 Aug 6;8(11):1629-39. doi: 10.1002/cphc.200700196.
Coordination complexes of the magnesium nitrate cation with water MgNO(3)(H(2)O)(n) up to n=7 are investigated by experiment and theory. The fragmentation patterns of MgNO(3)(H(2)O)(n) clusters generated via electrospray ionization indicate a considerable change in stability between n=3 and 4. Further, ion-molecule reactions of mass-selected MgNO(3)(H(2)O)(n) cations with D(2)O reveal the occurrence of consecutive replacement of water ligands by heavy water, and in this respect the complexes with n=4 and 5 are somewhat more reactive than their smaller homologs with n=1-3 as well as the larger clusters with n=6 and 7. For the latter two ions, the theory suggests the existence of isomers, such as complexes with monodentate nitrato ligands as well as solvent-separated ion pairs with a common solvation shell. The reactions observed and the ion thermochemistry are discussed in the context of ab initio calculations, which also reveal the structures of the various hydrated cation complexes.
通过实验和理论研究了硝酸镁阳离子与水形成的配位络合物MgNO(3)(H(2)O)(n)，其中n最大为7。通过电喷雾电离产生的MgNO(3)(H(2)O)(n)团簇的碎裂模式表明，n = 3和4之间稳定性有显著变化。此外，质量选择的MgNO(3)(H(2)O)(n)阳离子与D(2)O的离子 - 分子反应揭示了重水对水配体的连续取代现象，在这方面，n = 4和5的络合物比n = 1 - 3的较小同系物以及n = 6和7的较大团簇更具反应性。对于后两种离子，理论表明存在异构体，例如具有单齿硝酸根配体的络合物以及具有共同溶剂化壳的溶剂分离离子对。在从头算计算的背景下讨论了观察到的反应和离子热化学，该计算还揭示了各种水合阳离子络合物的结构。
