Add the tessellationless integration grid for the PCM as described in Pomelli 2004
This supersedes #65 which got outdated and impossible to rebase against the current release series.

Description

The GePol algorithm is based on a partition of the spheres that involves the use of spherical polygons. The TsLess algorithm uses a different strategy for the partition of the spheres that makes away with the polygons altogether in favor of just points and weights.

How Has This Been Tested?

• Comparison of the number of points, cavity surface and cavity volume with reference values. This is done for a single sphere, the HF and the NH3 molecules. TESTS CURRENTLY BROKEN
• Comparison of the total surface charge calculated with CPCM and IEFPCM with the exact value from Gauss' theorem. . This is done for a single sphere and the NH3 molecules. TESTS CURRENTLY BROKEN
  • We can compare our Leopardi partitioning of the spheres with the original EQP code
• Comparison of QM energies with those published in the original article.

Todos

• Developer Interest

• Symmetry-handling in the TsLess Fortran backend.
• Code duplication between the PEDRA and TsLess Fortran backends.

• User-Facing for Release Notes

• New cavity generator.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Questions

• Should we make TsLess the new default algorithm for cavity generation?

Status

• Ready to go