The CASINO forum

Hi Fan, Do you any example on using it? I'm afraid I don't. With CASSCF-Jastrow wavefunction in DMC, the result is improved, but still unsatisfactory. I would like to try some other trial wavefunction such as JAGP in DMC. Geminals and multigeminals remain very much untested. I would not expect to be...

Hi Fan, Each geminal in the MAGP wave function requires norb x norb parameters and a global coefficient. So if you have two orbitals in your basis, you would specify a single-geminal wave function in parameters.casl as: GEMINAL: Geminal 1: Parameters: c: [ 1.d0 , fixed ] g_1,1: [ 1.d0 , optimizable ...

Hi Fan,

Try setting:
in the input file, and see if that works.

Best,
Pablo

Hi Vladimir, In CASINO, the orbitals in each determinant are by default ordered sequentially, e.g., [123456], and excitations replace the specified orbital at its original position with the requested orbital, e.g., [123476]. The determinants are internally constructed strictly in this order. You nee...

Hi Vladimir, I see that in your first run you get the warning: Warning: [REDO_GAUSSIAN_ELIMINATION] non-linear parameters produce 1 zero(es) in the coefficient matrix for the constraint equations. We recommend that you stop this calculation, change the values of any basis parameters involved to non-...

Hi Vladimir, The parameters need to be in the MDET block in the correlation.data file (as you must have used to generate the mdet.casl file in the first place). The cmdet.casl file in only used to store the generic compressed expansion information, and the mdet.casl file is not read by CASINO. Best,...

Hi Ryan,

If I am not mistaken the energy quoted in the PRE is just the entry corresponding to the row labelled N2 and the column labeled E_e in Table 2 of https://doi.org/10.1080/00268970512331339323 .

Best,
Pablo

Hi Vladimir, Implementing backflow for g orbitals requires coding up the evaluation of the matrix of second derivatives of g Gaussians, i.e., d2/dx2, d2/dy2, d2/dz2, d2/dxdy, d2/dxdz, and d2/dydz of phi(r), in gauss_mol_bf.f90. This is regardless of which backflow terms you wish to use. Module gauss...

Hi Vladimir,

Yes, you can use both at the same time.

Best,
Pablo

Yup, and the leading order operation is the construction of the e-e-n term from e-e and e-n functions, so on paper the evaluation of the basis is not a significant contribution to the cost of evaluating the Jastrow factor (in practice things might be slightly different depending on the system, of co...