Starting from ADF2009.01 the meta-GGA's M06-L and TPSS can be used during the SCF. Also starting from ADF2009.01 the meta-GGA's can be used in combination with geometry optimization, TS, IRC, LT, numerical frequencies, and excitation energies (ALDA kernel used). All electron basis sets should be used.
The M06-L functional needs high integration accuracy (at least integration 7) for reasonable gradients. For TPSS moderate integration accuracy for reasonable gradients is sufficient. For heavier elements (Z>36) and if one uses the M06-L functional it is also necessary to include the following keyword
FragMetaGGAToten
Using this key FRAGMETAGGATOTEN the difference in the meta-hybrid or meta-GGA exchange-correlation energies between the molecule and its fragments will be calculated using the molecular integration grid, which is more accurate than the default, but is much more time consuming. Default is to calculate the meta-GGA exchange-correlation energies for the fragments in the numerical integration grid of the fragments.
