Binding energies of hexahydrated alkaline earth metal ions, M2+(H2O)6, M = Mg, Ca, Sr, Ba: Evidence of isomeric structures for magnesium [17]

Journal of the American Chemical Society

Volumn 121, Issue 9, 1999, Pages 1986-1987

  Rodriguez Cruz, Sandra E ^a   Jockusch, Rebecca A ^a   Williams, Evan R ^a  

^a UNIVERSITY OF CALIFORNIA   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ALKALINE EARTH METAL; BARIUM; CALCIUM; MAGNESIUM; STRONTIUM;

BINDING AFFINITY; DISSOCIATION; ENERGY; IONIZATION; LETTER; MASS SPECTROMETRY;

EID: 0033541042     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja983232v     Document Type: Letter

References (24)

1. (a) Castleman, A. W., Jr.; Bowen, K. H., Jr. J. Phys. Chem. 1996, 100, 12911-12944 and references therein.
2. (b) Keesee, R. G.; Castleman, A. W., Jr. J. Phys. Chem. Ref. Data 1986, 15, 1011-1071.
3. (c) Dzidic, I.; Kebarle, P. J. Phys. Chem. 1970, 74, 1466-1474
4. (d) El-Shall, M. S.; Schriver, K. E.; Whetten, R. L.; Meot-Ner (Mautner), M. J. Phys. Chem. 1989, 93, 7969-7973.
5. (e) Dalleska, N. F.; Honma, K.; Sunderlin, L. S.; Armentrout, P. B. J. Am. Chem. Soc. 1994, 116, 3519-3528.
6. (f) Berg, C.; Achatz, U.; Beyer, M.; Joos, S.; Albert, G.; Schindler, T., Niedner-Schatteburg, G.; Bondybey, V. E. Int. J. Mass Spectrom. Ion Processes 1997, 167/168, 723-734.
7. Schmelzeisen-Redeker, G.; Bütfering, L.; Röllgen, F. W. Int. J. Mass Spectrom. Ion Processes 1989, 90, 139-150.
8. (a) Peschke, M.; Blades, A. T.; Kebarle, P. J. Phys. Chem. A 1998, 102, 9978-9985.
9. (b) Blades, A. T.; Jayaweera, P.; Ikonomou, M. G.; Kebarle, P. J. Chem. Phys. 1990, 92, 5900-5906.
10. Spence, T. G.; Burns, T. D.; Guckenberger, V. G. B.; Posey, L. A. J. Phys. Chem. A 1997, 101, 1081-1092.
11. Rodriguez-Cruz, S. E.; Jockusch, R. A.; Williams, E. R. J. Am. Chem. Soc. 1998, 120, 5842-5843.
12. (a) Katz, A. K.; Glusker, J. P.; Beebe, S. A.; Bock, C. W. J. Am. Chem. Soc. 1996, 118, 5752-5763.
13. (b) Markham, G. D.; Glusker, J. P.; Bock, C. L.; Trachtman, M.; Bock, C. W. J. Phys. Chem. 1996, 100, 3488-3497.
14. Glendening, E. D.; Feller, D. J. Phys. Chem. 1996, 100, 4790-4797.
15. Pavlov, M.; Siegbahn, P. E. M.; Sandström, M. J. Phys. Chem. A 1998, 102, 219-228.
16. Price, W. D.; Schnier, P. D.; Williams, E. R. Anal. Chem. 1996, 68, 859-866.
17. (a) Price, W. D.; Schnier, P. D.; Jockusch, R. A.; Strittmatter, E. F.; Williams, E. R. J. Am. Chem. Soc. 1996, 118, 10640-10644.
18. (b) Dunbar, R. C.; McMahon, T. B.; Tholmann, D.; Tonner, D. S.; Salahub, D. R.; Wei, D. J. Am. Chem. Soc. 1995, 117, 12819-12825.
19. (a) Price, W. D.; Schnier, P. D.; Williams, E. R. J. Phys. Chem. B 1997, 101, 664-673.
20. (b) Jockusch, R. A.; Williams, E. R. J. Phys. Chem. A 1998, 102, 4543-4550.
21. -1 to take into account a range of transition state entropies.
22. Manuscript under preparation.
23. Relative energies for the hexahydrated metal ions were calculated using the hybrid density functional method B3LYP. Geometry optimizations were done using the double-ζ basis set LACVP**, which incorporates an effective core potential for Ca, Sr, and Ba (Hay, P. J.; Wadt, W. R. J. Chem. Phys. 1985, 82, 299-310) and uses 6-31G** for Mg, O, and H. Single-point energy calculations were done at the optimized geometries replacing the basis sets on Mg, O, and H with the larger 6-311G++(2d,2p) basis set. RHF frequency analyses confirmed that each structure is an energy minimum. Zero-point vibrational energies were calculated by scaling the RHF frequencies by 0.91. All of the calculations were performed using Jaguar v. 3.0 software (Schrodinger Inc., Portland, OR, 1997).
24. 2O) structures were studied; one in which the water in the second shell is hydrogen-bonded to one water in the inner shell, the other in which the outer water is hydrogen-bonded to two inner-shell water molecules. The latter structure is 4-6 kcal/mol more stable for all four hexahydrated metals.