# Are there any semiempirical methods that work with heavy alkaline earth metals?

I did some research. Found some semiempirical methods that work even with heavy lanthanide compounds (RM1). But could not find any references to semiempirical methods compatible with the heavier members of the alkali earth group: Sr, Ba and Ra. If there is such method, does any open source / free software implements it? I'm learning to use Gamess-US, but the only semiempirical methods implemented in this package are MNDO, AM1, PM3 and RM1 (refs file).

• Good answer! For future reference: I fixed your links, they should be terminated with a space. Additionally you can use the [text](url) construct for inline links. There is also a [text][ref] construct. Please see the help pages for more information. – Martin - マーチン Mar 21 at 15:57