Hello all

It is well known that for effective DMC calculation one need, among other things, to choose the optimal time-step. Fort all-electron atomic systems, the linear regime to occur for time steps less than of the order

τ= 1/(3Z^2), where Z is the largest atomic number occurring in the system.

https://www.ncbi.nlm.nih.gov/pubmed/21797515

If we have one heavy atom in the molecule optimal time-step have to be very small also for all other atoms.

However, a solution was proposed for this problem by C.J.Urigar https://journals.aps.org/prl/abstract/1 ... ett.71.408 - an accelerated Metropolis algorithm, wherein each electron attempts moves that are proportional to its distance from the nearest nucleus.

Further improvement and generalization of this method was proposed in the article http://aip.scitation.org/doi/abs/10.1063/1.476862

As far as I noticed in CASINO, none of the two approaches described above is implemented.

How difficult to implement one of and whether there are any plans for this?

Best Vladimir.