The energy and its analytic gradient are developed for the solvation model density (SMD) combined with the fragment molecular orbital (FMO) method. The accuracy of the energy is evaluated in comparison to full results without fragmentation for a set of neutral and charged polypeptides. The accuracy of the gradient is computed in comparison to numerical gradient. The components to the solvation energy in SMD are compared to the polarizable continuum model (PCM). FMO with SMD and PCM is applied to analyze protein–ligand binding in solution.

中文翻译：

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使用溶剂化模型密度结合碎片分子轨道方法分析溶质与溶剂的相互作用

为溶剂化模型密度（SMD）结合碎片分子轨道（FMO）方法开发了能量及其解析梯度。与完整结果相比，评估了能量的准确性，对于一组中性和带电多肽而言，没有分段的完整结果。与数字梯度相比，计算了梯度的精度。将SMD中溶剂化能量的成分与可极化连续体模型（PCM）进行了比较。带有SMD和PCM的FMO用于分析溶液中的蛋白质-配体结合。