[1] Univ Minnesota, Dept Chem, Ctr Theory, Minneapolis, MN 55455 USA
[2] Univ Minnesota, Dept Chem Engn, Ctr Theory, Minneapolis, MN 55455 USA
[3] Univ Minnesota, Dept Mat Sci, Ctr Theory, Minneapolis, MN 55455 USA
[4] Univ Minnesota, Dept Chem, Ctr Theory, Minneapolis, MN 55455 USA
[5] Argonne Natl Lab, Leadership Comp Facil, Argonne, IL 60439 USA
[6] Rice Univ, Dept Bioengn, Houston, TX 77005 USA
[7] Rice Univ, Dept Phys & Astron, Houston, TX 77005 USA