%0 Journal Article
%@ 1520-6106
%A Choi, TH
%A Jordan, KD
%D 2010
%F pittir:16169
%J Journal of Physical Chemistry B
%N 20
%P 6932 - 6936
%T Application of the SCC-DFTB method to H<sup>+</sup>(H<inf>2</inf>O) <inf>6</inf>, H<sup>+</sup>(H<inf>2</inf>O)<inf>21</inf>, and H<sup>+</sup> (H<inf>2</inf>O)<inf>22</inf>
%U http://d-scholarship-dev.library.pitt.edu/16169/
%V 114
%X The low-lying potential energy minima of the H+(H2O) n, n = 6, 21, and 22, protonated water clusters have been investigated using two versions of the self-consistent-charge density-functional tight-binding plus dispersion (SCC-DFTB+D) electronic structure methods. The relative energies of different isomers calculated using the SCC-DFTB+D methods are compared with the results of DFT and MP2 calculations. This comparison reveals that for H+(H2O)6 the SCC-DFTB+D method with H-bonding and third-order corrections more closely reproduces the results of the MP2 calculations, whereas for the n = 21 and 22 clusters, the uncorrected SCC-DFTB+D method performs better. Both versions of the SCC-DFTB+D method are found to be biased toward Zundel structures. © 2010 American Chemical Society.