Iozzi Maria Francesca, Cossi Maurizio, Improta Roberto, Rega Nadia, Barone Vincenzo
Dipartimento di Chimica, Università Federico II, Complesso Monte S. Angelo, via Cintia, I-80126 Napoli, Italy.
J Chem Phys. 2006 May 14;124(18):184103. doi: 10.1063/1.2188392.
We present a computational method, exploiting some features of the polarizable continuum model (PCM) to describe heterogeneous media; it belongs to the family of electrostatic embedding mixed methods, such as the more common quantum-mechanical (QM)/molecular mechanics approaches, with the electrostatic long range effects accounted for by a polarized continuum instead of atomic point charges. Provided effective dielectric constants are determined for the various parts of the system, the method is much faster than its atomistic counterpart, and allows for high-level QM calculations on the fragment of interest, using all the highly efficient computational tools developed for homogeneous PCM. Two case studies (the calculation of the pKa of solvent exposed acidic residues in a model protein, and the calculation of the electron spin resonance spectrum of a typical spin probe partially embedded in a membrane) are analyzed in some detail, to illustrate the application of the method to complex systems.
我们提出了一种计算方法，利用可极化连续介质模型（PCM）的一些特性来描述非均匀介质；它属于静电嵌入混合方法家族，例如更常见的量子力学（QM）/分子力学方法，其中静电长程效应由极化连续介质而非原子点电荷来考虑。只要为系统的各个部分确定了有效的介电常数，该方法就比其原子模型对应方法快得多，并且允许使用为均匀PCM开发的所有高效计算工具，对感兴趣的片段进行高水平的QM计算。详细分析了两个案例研究（模型蛋白质中溶剂暴露酸性残基的pKa计算，以及部分嵌入膜中的典型自旋探针的电子自旋共振光谱计算），以说明该方法在复杂系统中的应用。
