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the results (optimized correlation .out0, 1, 2, ..) are not the same as the defaulte correlation.data for this example. I know that. To repeat the question, what exactly are the results with the default correlation.data that you are comparing with? i.e. the actual numbers. Obviously it won't be exa...

Hi Samaneh,

Before I answer, when you say 'the results are not the same as the real correlation.data' - what exactly are the results for the 'real correlation.data' given in the examples?

Best wishes,
Mike

Good point. I'll adjust the documentation so that it's clearer how to specify spin.

M.

> BTW, I found that there is a parameter jastrow_plot, which may help in finding whether Jastrow is reasonable, but how to use it? (especially, > how to tell Casino the spins of particles)? Typing 'casinohelp jastrow_plot' will tell you the syntax of the input block, including the particle spins. > ...

Hi Samaneh, If you set the Jastrow cutoffs to zero in the correlation.data file, they will be given suitable default values (they can be optimized later if you wish). To make a 'starting Jastrow', find any sections labelled 'Parameter values' and delete all the numbers that follow that label. Optimi...

Dear Saeed, This is actually a good question, not least because the documentation is not clear on which expectation values are computable for which kinds of system. So I've just trawled through and updated the documentation (both the manual and the internal keyword listings) and now it hopefully is ...

And, I forgot to mention - if you get population explosions in DMC, then make the timestep dtdmc smaller (having first made sure the Jastrow optimization was done properly and gives sensible answers). If explosions occur very frequently, you can use the catastophe recovery facility enabled via the d...

Hello varelse, As you know, Hartree-Fock doesn't attempt to compute the true energy - just the lowest energy consistent with the assumption of a single determinant wave function, which is always higher than the true (non-relativistic) energy unless you're talking about a hydrogen atom. The differenc...

Hi Mauro, So the purpose of CRYSTAL here is to define the 1x1x1 'primitive' cell for CASINO, and as far as CASINO is concerned that is defined just by the lattice vectors that CRYSTAL sends to it via the gwfn.data file. You can construct these lattice vectors as an arbitrary linear combination of th...

And an additional point which occurs to me. The guy who wrote the CASINO-GAUSSIAN interface (Andrew Porter) was a student with us about 12 years ago at which point the GAUSSIAN periodic implementation was either non-existent or not working very well and so he will have ignored it. So the converter p...