VCA for the sum of the pseudopotential coefficients must 1

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onion2440
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Joined: Sat Sep 05, 2015 10:04 am

VCA for the sum of the pseudopotential coefficients must 1

Post by onion2440 » Fri Mar 25, 2016 10:26 am

Dear everyone,
I want simulate the oxygen concentration using VCA(Virtual-crystal approximation )method with the input parameters showing below.
ntypalch 3
mixalch 0.999999999999 0.000000000001 0 0 0 0
0 0 0.0 0.88 0 0
0 0 0 0 0.0 0.88
But now i encount the errors:
--- !ERROR
message: |
For the alchemical atom number 2
the sum of the pseudopotential coefficients is 0.88
while it should be one.
Action : check the content of the input variable mixalch.
src_file: ingeo.F90

I wanna know why the coefficients should be 1?
any answer should be helpful!
sincerely
onion2440

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