Jastrow optimisation, the default in 2.12

General discussion of the Cambridge quantum Monte Carlo code CASINO; how to install and setup; how to use it; what it does; applications.
Philip_Hoggan
Posts: 17
Joined: Thu Sep 05, 2013 2:09 pm

Re: Jastrow optimisation, the default in 2.12

Post by Philip_Hoggan »

Have not finished optimising the Jastrow for the H2 adsorbed on Cu(111) slab but observed the following, which is annoying and wanted to know if it is usual or the sign of a deeper problem.

The variance for the whole system is now 182 Ha (712 electrons).

If I remove the H2 and do not reoptimise the Jastrow at all (just keep the copper part), I get, for the clean surface, a variance of 118 Ha (704 electrons)

Its a 2 2 1 grid, so there are 4 H2 horizontal above the surface, at long distance in this case.

Best,

Philip
Philip_Hoggan
Posts: 17
Joined: Thu Sep 05, 2013 2:09 pm

Re: Jastrow optimisation, the default in 2.12

Post by Philip_Hoggan »

The previous post compared incomparable wave-functions: the values with blips expanded to order 1.5 are:

118Ha (clean copper)

124 Ha (copper with 4 H2 molecules 6A away)
Mike Towler
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Location: Florence
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Re: Jastrow optimisation, the default in 2.12

Post by Mike Towler »

Hi Philip,

I think you're trying to say that your wave function optimization didn't work.

For us to make a useful comment, we need way more information.. :D

M.
Philip_Hoggan
Posts: 17
Joined: Thu Sep 05, 2013 2:09 pm

Re: Jastrow optimisation, the default in 2.12

Post by Philip_Hoggan »

Dear Mike,

There are two wavefunctions, one for a stretched H2 bond (adsorbed on Cu(111)) and the other for H2 in equilibrium geometry 6A from the Cu(111) slab.

I am not satisfied with either but find the latter particularly suspicious (compared with the separated H2 and clean surface). I've been trying to re-do the optimisation, using the approach suggested by Neil to work on a real wavefunction but cannot get inversion symmetry without serious modifications.

So, what info do you need? The blips and correlation data? The geometries?

Best,

Philip
Mike Towler
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Re: Jastrow optimisation, the default in 2.12

Post by Mike Towler »

The input file, the out file, and the collection of correlation.out.x files resulting from the optimization would be a good start. We don't need the wave function file etc. yet..

M.
Mike Towler
Posts: 239
Joined: Thu May 30, 2013 11:03 pm
Location: Florence
Contact:

Re: Jastrow optimisation, the default in 2.12

Post by Mike Towler »

In order to bring this thread to some sort of conclusion, I post here a PS from a subsequent email sent to me by Philip:

"PS regarding the Jastrow optimisation pb, I think I've found what went wrong and am doing some tests but may send it all to you since I cannot see how it happened."

M.
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