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MP2 Properties


How do I calculate MP2 properties?

The default molecular orbital file $file_prefix$.movecs is used unless a VECTORS subdirective is provided in the PROPERTY directive. It is therefore necessary to include a VECTORS directive if the MO vectors to be analyzed are not coming from the default file, e.g., if they have been previously redirected, or if MP2 natural orbitals (file extension ".mp2nos") are being anaylzed. So, to calculate MP2 properties, a PROPERTY block directive similar to the one in the following example would be appropriate:

      start h2o
      title; Water MP2 properties example

      geometry
        O 0  0     0
        H 0  1.430 1.107
        H 0 -1.430 1.107
      end

      basis
        H library sto-3g
        O library sto-3g
      end

      task mp2

      property
        octupole
        efield
        vectors h2o.mp2nos
      end

      task property
 


My high symmetry MP2 calculation is taking longer that it should. Why is this?

Currently MP2 can only use Abelian point groups and does not have descent of symmetry implemented (meaning that it does not know how to use a proper Abelian point group instead of an input non-Abelian group). The user must define the proper Abelian point group, orient the molecule into this point group, and then run the MP2.


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Updated: February 22, 2005