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The Jastrow factor redistributes the electron density from where the probability of two electrons meeting is higher to where it is lower, so a term is needed that will redistribute it back. Such a term (chi-term) is usually included and depends on the distance of the electron to the nucleus, since s...

Please accept my sincere congratulations on this epochal event!
Could you also provide an example config file and a link to updated documentation?


Vladimir.

Hello Mike. I was wondering why we convert Cartesian GTO to solid-harmonic ones, and not the other way around? After all, the calculation of the wave function and its partial derivatives is simpler for Cartesian and maybe Hermitian GTO. WIREs Comput Mol Sci 2012, 2: 290–303 doi: 10.1002/wcms.78 eq. ...

Unfortunately, the calculation of 3-rd partial derivatives of the slater determinant w.r.t e-coordinates do not fit in the L1/L2 cache even for moderately large system like Kr-atom. I ran perf stat -e instructions,cache-misses <executable> and confirmed my assumptions. I don't see such cache-misses ...

Hello Casino developers. While reading the CASINO documentation I discovered: Gaussian basis functions can be regarded as localized if they are truncated to zero outside a certain radius. This is done by default in casino: Gaussian functions exp(−ar²) are assumed to be zero when exp(−ar²) < 10^-GT ,...

Hello Neil. I want to compare k independent DMC simulations with n configurations each m/n_proc steps vs one DMC simulation with n configurations m steps. For example n = 1024, m = 100000, n_proc = 32. This requires same time ~n*m/n_proc and gives the same accuracy ~sqrt(n*m), but takes n_proc times...

Hello CASINO developers. I can suggest a multi-threaded method without loadbalancing для DMC. This method includes the following steps (for n configurations, m dmc accumulate steps and k processes): In any process do: 1. create n configurations in VMC run 2. equlibrate n configurations in DMC equlib...

Hello Casino developers. I noticed the latest changes in the program: * stowfdet.f90: implemented g functions; added mdet support; fixed bugs -- Pablo Lopez Rios, 2024-03-29 This includes: * Coded up support for g functions (derivatives were missing), including sderivs for backflow. * Coded up const...

A good way to check if the orbitals have been parsed correctly is to compute the molecular orbital overlap matrix, which should give you the identity matrix. The overlap matrix is also very cheap to compute, even for large systems. I think it's worth doing this check.

Great to read you, Mike. The manual says 6.1.2 Pseudopotentials: On the rare occasions when you might want to use two or more different pseudopotentials for atoms with the same atomic number (say in a surface, and in an atom or molecule absorbed on that surface), then you may use additional pseudopo...