Table 1.

Overview of the integrals that can be neglected (denoted with an ×) when considering QM, QM∕MM, and MM∕MM blocks of the Hessian matrix.

	QM-QM	QM-MM∕MM-QM	MM-MM
PHxy	√	√	√
P∥xyP	√	×	×
(PFP)Sxy	√	×	×
PyHx	√	√	√
Py∥xP	√	√	×
(PFP)ySx	√	√	×
γxy	√	√	√