Peng Yong, Kaminski George A
Department of Chemistry, Central Michigan University, Mount Pleasant, Michigan 48859, USA.
J Phys Chem B. 2005 Aug 11;109(31):15145-9. doi: 10.1021/jp0511956.
OPLS-AA force field and direct integration of intermolecular radial distribution functions (RDF) were employed to calculate absolute binding constants of pyridine molecules to amino group (NH2) and amide group hydrogen atoms in and first generation poly(amidoamine) dendrimers in chloroform. The average errors in the absolute and relative association constants, as predicted with the calculations, are 14.1% and 10.8%, respectively, which translate into ca. 0.08 and 0.06 kcal/mol errors in the absolute and relative binding free energies. We believe that this level of accuracy proves the applicability of the OPLS-AA, force field, in combination with the direct RDF integration, to reproducing and predicting absolute intermolecular association constants of low magnitudes (ca. 0.2-2.0 range).
采用OPLS - AA力场和分子间径向分布函数（RDF）的直接积分方法，计算吡啶分子与第一代聚（酰胺 - 胺）树枝状大分子中氨基（NH₂）和酰胺基氢原子在氯仿中的绝对结合常数。计算预测的绝对和相对缔合常数的平均误差分别为14.1%和10.8%，这相当于绝对和相对结合自由能的误差约为0.08和0.06千卡/摩尔。我们认为，这种精度水平证明了OPLS - AA力场与直接RDF积分相结合，适用于再现和预测低量级（约0.2 - 2.0范围）的绝对分子间缔合常数。
