[Pw_forum] Non zero "Effective Charges" of Silicon in "example02"

[xirainbow]

Dear all:

             I ran the "example-4.3.2/examples/example02" and got the
"si.dynG" file.
             In the "si.dynG" file, the "Effective Charges of Silicon" was :
*"     Effective Charges E-U: Z_{alpha}{s,beta}*
*     atom #    1*
*         -0.075683653870          0.000000000000          0.000000000000*
*          0.000000000000         -0.075683653870          0.000000000000*
*          0.000000000000          0.000000000000         -0.075683653870*
*     atom #    2*
*         -0.075683653870          0.000000000000          0.000000000000*
*          0.000000000000         -0.075683653870          0.000000000000*
*          0.000000000000          0.000000000000         -0.075683653870*
*"*
            Obviously, the "Effective Charges" of the two atoms do not
satisfy the "sum rule".
            Can I take  -0.075683653870 as zero?  If so, what is the
precision of  calculated  "Effective Charges" ?

            Thanks in advance ：）

-- 
____________________________________
Hui Wang
School of physics, Fudan University, Shanghai, China
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