Fragmentation methods reproduce the result of the exponential scaling full system calculation within an error about 1 kcal/mol. They serve as a robust linear scaling regime of quantum treatment for large molecular systems. As the response of fragmentation methods to convergence criteria in SCF iterations is different from that of full system calculation and the propagated convergence error is much smaller than the fragmentation error, the speed of fragmentation ab initio calculation can be further enhanced via loosening the convergence criterion in the calculation of each fragment without sacrificing the accuracy of the overall energy. Tests on single configuration calculations, geometry optimization and molecular dynamics simulation are performed.

中文翻译：

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碎片方法收敛准则的优化

片段化方法可在整个系统中以指数比例缩放的结果重现约1 kcal / mol的误差。它们可作为大分子系统量子处理的可靠线性缩放方案。由于SCF迭代中碎片化方法对收敛准则的响应不同于完整系统计算的结果，并且传播的收敛误差远小于碎片化误差，因此通过松散收敛准则可以进一步提高碎片从头计算的速度。在不牺牲总能量精度的情况下计算每个碎片。对单一构型计算，几何优化和分子动力学模拟进行测试。