Their is a paper to the xlogp: Wang, R, Ying, Fu, & Lai, Luhua, As I rememeber they have a fragment like approach and the para H Fragment is not
be taken into account with the cdk implementation. But I am not quite sure, have
to read it again by myself ;).
the documentation is not complete...I mean there is only one example. I'm still waiting an email from Dr Wang with the original source code for a complete validation.