Subject: ECP & bond orders

From: "Ananikov V.P." <[email-masked]>
Date: Thu, 20 Nov 1997 10:17:41 -0800

Dear CCL’s,

I would be glad to receive your comments concerning this problem:
When I perform ECP calculations on simple transition metal ions, such 
as PtCl5(-), PtCl6(2-), PtI6(2-), etc., Bond Order Analysis sometimes 
gives small bond order values between nonbonded atoms, i.e. Cl-Cl, I-I.
The bond order values are typically in the range of 0.08-0.1
Might it have a reasonable explanation?
I am using Stevens-Basch-Krauss-Cundari ECP’s as implemented in GAMESS
package.

Since this is observed only with ECP bases set, the answer to the next
rather general question is also of interest:
Does the 'Bond Order' conception in the case of core-potential involved
mean exactly the same as for all-electron calculations?

thank you.

I will summarize.

sincerely,
Valentin.

===============================================================

Valentin P. Ananikov

NMR Laboratory
N.D. Zelinsky Institute of Organic Chemistry
Leninsky Prospect 47
Moscow  117913, Russia

                                    e-mail: [email-masked]
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