[molpro-user] Fwd: C8 disp coefficient

[Tatiana Korona]

Dear Yulia,

First of all, these are not EOM-CCSD calculations, but rather XCCSD 
dynamic polarizability calculations.

I think that this link from molpro-user can be useful for you
http://www.molpro.net/pipermail/molpro-user/2005-July/001440.html
where definitions of Molpro second moments and quadrupole moments are discussed.

Best wishes,

Tatiana

On Sun, 16 Jun 2013, Yulia Kalugina wrote:

>

Dear molpro community,

May be someone could help me with the obtaining of C8_000 dispesion coefficient from EOM-CCSD calculations?


Here is an example for N2-N2:

Uning proparator methof of Tatiana Corona we obtain <X;Y>:
a6633 := 136.6805842; 
a4433 := 78.70125049; 
a5533 := 78.70125049; 
a5633 := -68.34029205;
a4633 := -68.34029205; 
a4533 := -10.36095844; 
a8833 := 97.21710728; 
a8811 := 70.14620802; 
a4411 := 57.06216406;
a5511 := 57.06216406; 
a4511 := -7.578876794; 
a6611 := 98.96657460; 
a5611 := -49.48328727;
a4611 := -49.48328727;
as i understand, a6633=<zz,zz;zz> (for example). 
here 
1 - x
2 - y
3 - z
4 - xx
5 - yy
6 - zz
7 - xy
8 - xz
9 - yz
...


after, we have an expression for X integrals: 
X2100=1/4(4*a6633+a4433+a5533-4*a5633-4*a4633+2*a4533)
X2101 ....

But when I use the formula for C8 isotropic coefficient, I have not obtained correct results (I obtain 4775 instead of correct value around 2500). 
C000_8=X2100+2*X2101+2*X2110+4*X2111+2*X2120+4*X2121+X1200+2*X1201+2*X1210+4*X1211+2*X1202+4*X1212
(Ref. J Comput Chem 32: 279–290, 2011  :  "Long-Range Interaction for Dimers of Atmospheric Interest: Dispersion, Induction and Electrostatic Contributions for O2–O2, N2–N2 and O2–N2")

May be someone can indicate where is a mistake. For C6 coefficients I have no problems.

I would be very appreciated any help.

Best regards,

Yulia KALUGINA 
LOMC - Université du Havre 
25 Rue Philippe Lebon 
BP 540 - 76 058 Le Havre cedex FRANCE 
tel:  +33 (0)2 35 21 71 03 
--------- 
OS - Tomsk State University 
36, Lenina av. 634050 Tomsk RUSSIE 
Mail : yulia.kalugina at univ-lehavre.fr , kalugina at phys.tsu.ru


----------------------------------------------------------------------

ICQ Number:  429-874-882

Dr. Tatiana Korona http://tiger.chem.uw.edu.pl/staff/tania/index.html
Quantum Chemistry Laboratory
University of Warsaw
Pasteura 1, PL-02-093 Warsaw, POLAND


`The man who makes no mistakes does not usually make anything.'
                                        Edward John Phelps (1822-1900)