- ...density
- It was shown by
Harriman[12] that all densities are N-representable
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- ...choice
- The choice of g(x)=|f(x)| minimises the
variance of the estimate of the integral
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- ...energy,
- For silicon the total energy per atom is of the
order of -107eV and the contribution from the non-local part of the
pseudopotential is of the order of 2eV per atom (with p local).
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- ...itself.
- The
fixed-node approximation does depend on the guiding wavefunction.
None of the optimisation here changes the nodal structure because the
Slater determinant is not being optimised.
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- ...N
- In the limit of an infinitely large simulation cell the
residual value of the CFSE reflects the fact that different choices of
the boundary conditions at infinity give total energies which differ
by a finite amount.
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- ...hole
- Calculations of
pair correlation functions [74] show they converge rapidly
with simulation cell size.
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- ...approximation
- Note that a
successful QMC calculation requires a reasonable approximation to the
wavefunction itself, so that the requirement of a reasonable
approximation to the charge density is not a serious limitation.
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- ...affinity
- Strictly, the electron affinity of the N electron
system is defined as 597#597
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- ...it
- This is achieved by reducing
the distances to all the other electrons into the Wigner-Seitz cell
centred on the electron being considered.
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