ESTOP

ESTOP = [real]

Default: ESTOP

= 0.05

Description: ESTOP specifies the stop condition for stochastic MP2.

ESTOP defines the energy accuracy in units of eV for each individual tau-point of the two individual MP2 energy contributions (direct MP2 term + exchange MP2 term). Since the statistical errors of each contribution is independent, the standard deviation of the MP2 energy can be estimated as

[math]\displaystyle{ \sigma = \texttt{ESTOP} * \sqrt{2 \cdot \texttt{NOMEGA}} \;. }[/math]

According to our experience, the error of the resulting MP2 energy can then be safely estimated by [math]\displaystyle{ \pm 2 \sigma }[/math].

Thus, if you require an MP2 energy with a maximum error of [math]\displaystyle{ \Delta }[/math], you should set

[math]\displaystyle{ \texttt{ESTOP} = \frac{\Delta}{2 \cdot \sqrt{2 \cdot \texttt{NOMEGA}}} \;. }[/math]

See this tutorial for more Information about Laplace transformed MP2.

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