Subject: Re: Theoretical Calculations of Lanthanide Organic Complexes

From: Gustavo Mercier <[email-masked]>
Date: Tue, 31 Aug 1993 13:27:40 -0400 (EDT)

On 30 Aug 1993, Nivan Bezerra wrote:

> Dear Netters,
> 
> 	I am interested in theoretical methods for the calculations of
> organic complexes of lanthanides, especially Eu(III).
> 	Does anyone know any packages for this type of calculation using
> MO, extended Huckel, Xalpha, Density Functional Theory, INDO, AMPAC,
> MOPAC, etc?
> 	Thank you very much.

You may try several things:

	1) Standard packages like G92, Hondo, GAMESS etc using effective
core potentials that include relativistic effects in an "average" fashion.
See below for references regarding ecp's for lanthanides and other atoms.

	2) You may try DFT computations. A package like ADF from Baerends
group includes a "basis set" for Eu and you can include relativistic effects.
You may contact them to obtain the program (1500 DG fro academic users)-
[email-masked] or [email-masked]

Regarding semiempirical methods I am unfamiliar with programs that have
parameterized the Lanthanides. Anybody aware of such program?

Good Luck!

Gus Mercier
[email-masked]

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The following references should provide you with very recent ECP's for
most of the periodic table. The comments I have heard from those who
have used them are rather favorable (comments limited to energetics and
geometries):

	Stevens et. al. J. Chem.Phys. 81 (12), Pt. II, 1984
	First and Second Row atoms

	Stevens et. al. Can. J. Chem. 70, 612, (1992)
	Third through Fifth row atoms. Some typos are known:

	Table 2: In RECP for second Vp-f component:
			-129.87594 should read -129.78594
	Table 4: Basis for Fe
			Cp term for 1sp should be -0.007940, not -0.07940
			asp term for 4sp should be 0.0410, not 0.410
	Table 7: Result for Be
			Eval with core a should read -1.01214, not -0.01214

	Cundari and Stevens J. Chem. Phys. 98 (7) 1993
	Lanthanides

I hope this is useful. These papers also discuss the variety of methods
available to generate ECP's, relativistic effects and references to ECP's
for DFT computations.

Good Luck
gus mercier
[email-masked]