Charge asymmetries in hydration of polar solutes. Export

@article{citeulike:2341612, abstract = {We study the solvation of polar molecules in water. The center of water's dipole moment is offset from its steric center. In common water models, the Lennard-Jones center is closer to the negatively charged oxygen than to the positively charged hydrogens. This asymmetry of water's charge sites leads to different hydration free energies of positive versus negative ions of the same size. Here, we explore these hydration effects for some hypothetical neutral solutes, and two real solutes, with molecular dynamics simulations using several different water models. We find that, like ions, polar solutes are solvated differently in water depending on the sign of the partial charges. Solutes having a large negative charge balancing diffuse positive charges are preferentially solvated relative to those having a large positive charge balancing diffuse negative charges. Asymmetries in hydration free energies can be as large as 10 kcal/mol for neutral benzene-sized solutes. These asymmetries are mainly enthalpic, arising primarily from the first solvation shell water structure. Such effects are not readily captured by implicit solvent models, which respond symmetrically with respect to charge.}, address = {Department of Pharmaceutical Chemistry, and Department of Biopharmaceutical Science, University of California at San Francisco, San Francisco, California 94143}, author = {Mobley, D. L. and Barber, A. E. and Fennell, C. J. and Dill, K. A.}, citeulike-article-id = {2341612}, citeulike-linkout-0 = {http://dx.doi.org/10.1021/jp709958f}, citeulike-linkout-1 = {http://pubs.acs.org/doi/abs/10.1021/jp709958f}, citeulike-linkout-2 = {http://view.ncbi.nlm.nih.gov/pubmed/18251538}, citeulike-linkout-3 = {http://www.hubmed.org/display.cgi?uids=18251538}, day = {28}, doi = {10.1021/jp709958f}, issn = {1520-6106}, journal = {The journal of physical chemistry. B}, keywords = {beyond\_pb, implicit\_solvation, water\_models}, month = {February}, number = {8}, pages = {2405--2414}, posted-at = {2008-02-08 19:36:13}, priority = {4}, title = {Charge asymmetries in hydration of polar solutes.}, url = {http://dx.doi.org/10.1021/jp709958f}, volume = {112}, year = {2008} }

TY - JOUR ID - citeulike:2341612 L3 - citeulike-article-id:2341612 N2 - We study the solvation of polar molecules in water. The center of water's dipole moment is offset from its steric center. In common water models, the Lennard-Jones center is closer to the negatively charged oxygen than to the positively charged hydrogens. This asymmetry of water's charge sites leads to different hydration free energies of positive versus negative ions of the same size. Here, we explore these hydration effects for some hypothetical neutral solutes, and two real solutes, with molecular dynamics simulations using several different water models. We find that, like ions, polar solutes are solvated differently in water depending on the sign of the partial charges. Solutes having a large negative charge balancing diffuse positive charges are preferentially solvated relative to those having a large positive charge balancing diffuse negative charges. Asymmetries in hydration free energies can be as large as 10 kcal/mol for neutral benzene-sized solutes. These asymmetries are mainly enthalpic, arising primarily from the first solvation shell water structure. Such effects are not readily captured by implicit solvent models, which respond symmetrically with respect to charge. IS - 8 JF - The journal of physical chemistry. B SN - 1520-6106 AD - Department of Pharmaceutical Chemistry, and Department of Biopharmaceutical Science, University of California at San Francisco, San Francisco, California 94143 EP - 2414 TI - Charge asymmetries in hydration of polar solutes. VL - 112 SP - 2405 KW - beyond_pb KW - implicit_solvation KW - water_models AU - Mobley, DL AU - Barber, AE AU - Fennell, CJ AU - Dill, KA PY - 2008/02/28/ UR - http://dx.doi.org/10.1021/jp709958f ER -