Subject: G92-DFT bug? H and LYP

From: [email-masked] (Thomas Fox)
Date: Thu, 2 Feb 95 12:13:03 "PST

Dear CCLers,

I was using the DFT module of Gaussian 92 (HP-PARisc-HPUX-G92/DFT-RevF.4)
and came across something that looks like a bug to me: when I try to
calculate an one-electron system (like the H atom) and use the Lee-Yang-Parr
functional, my G92 version stops with an IEEE division by zero error.
I browsed through the code, and sure enough found in the LYP subroutine
a division by Rho(Beta), which is, in the case of one electron, equal zero.
I dont have access to the original paper right now, so could someone just
reassure me that this behavior is definitely an unexpected one, and that
it doesnt mean that the LYP functional is not valid in the limit of one
electron or if I only have electrons of one spin species (Gaussian shouldnt 
abort that ungracefully, anyway...).

A related question is how to get in contact with these Gaussian guys...I
sent a message to [email-masked] some weeks ago, but havent heard from 
them back.

And, could anybody who has access to a DFT implementation (maybe there is
even a G92 version out there that doesnt show this behavior) that 
supports Becke 3 parameter XC in connection with the LYP C functional
calculate the energy for a H radical (with a 6-31G* basis) for me? Pointers
to papers where this has been done (maybe as a test case for the functional)
are, of course, also highly welcome.

Thanks a lot,

Thomas
--

Thomas Fox                               e-mail: [email-masked]
Dept. of Pharmaceutical Chemistry
University of California
San Francisco, CA 94143-0446
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