306 reputation
15
bio website molecular.cz/~fackovec
location Prague, Czech Republic
age 24
visits member for 2 years, 3 months
seen Jan 10 '13 at 17:45

May
9
comment Density of classical states in quantum theory
@Ron: postHF = post-Hartree-Fock
May
9
comment Density of classical states in quantum theory
@genneth: DFT is exact only theoretically. noone has ever found correct functional. it is like telling that using configurational integral is exact solution, but it is just rephrasing the problem.
Apr
24
comment Density of classical states in quantum theory
DFT is an approximation often called an expensive RNG. I talk about some precise stuff, exact wavefunction. Not those coupled cluster or PIMC approximations.
Apr
10
comment How to find that a molecule has zero spin?
Pauli exclusion priciple implies only that only 2 electrons can occupy 1 orbital. Energetic degeneracy of more distinct orbitals can cause some orbitals to be only singly occupied. There is also a Hund principle of maximum multiplicity (electrons having same spin repel less each other resulting in lower energy). So not all atoms/ions/compounds with even number of electrons have zero spin.
Apr
10
comment What formulae for calculating fluid pressure change involves these parameters?
It seems to be volumetric flow. I do not see viscosity in the formula.