[Pw_forum] Question on the pseudopotential generation using LD1

[张 洪彬]

Dear all,
Wish you have a happy New Year first.
Now I want to do some Virtual Crystal Approximation calculation where Mg 
pseudopotentials must be generated, however I am a little confused with 
those parameters showed in the INPUT_LD1, thus my first question is where 
can I find some general introduction on pseudopotential generation? please 
refer me to some papers.

Following the example of al.in, I wrote an input file for pseudo-gen of Mg, 
but there is an error as follows:
                                                       no error in all 
electron calculation
__________________________________________________________________________
Generating local potential, lloc =-1 (while =2 there's the same error)

Local pseudo, rcloc= 1.500 Estimated cut-off energy=  10.49Ry
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
from compute phi :error #   -1
negative determinant
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

                       1 ld = 1.168338 f2ae -0.660044 faenor 0.060527

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
                          from gener_pseudo : error # 1
                            too many nodes
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
If I change "rcut" from 1.50(which resulted in the error above) to 2.00 or 
3.00, there would be an error massege said that  at the begginning like 
this:
   This function has  0 nodes for 0 < r < 1.994
While " too many nodes" shows too,  so what's the problem?

Further more, if I want to consider transition metal doping of Mg,  it is 
obvious that d electrons should be considered, then can I inculde d 
electron in Mg electron configuration, which may like this:
    [Ne] 3S1 3d0.5 4S1
and correspondingly zed=(1-x)* 12 + x* Z , where Z is the nuclear charge of 
the doped element, x is the doping percentage. Is this correct?

Thank you very much and have a nice day.
Best regards
Hongbin Zhang 

PS: input file for Mg pseudo-gen
&input
     title='Mg',
     zed=12.0,
     rel=0,
     beta=0.5,
     rlderiv=2.4,
     eminld=-4.0,
     emaxld=8.0,
     deld=0.02d0,
     nld=3,
     config='[Ne] 3s2 3p-1 ',
     iswitch=3,
     dft='LDA',
 /
 &test
    pseudotype=1,
    nconf=1,
 / 
1
3S  1  0  2.00  0.00  2.00  2.00  1
 &inputp
   lloc=-1,
   file_pseudopw='Mg.rrkj3',
   zval=2.d0,
 /
2
3S  1  0  2.00  0.00  1.50  1.50
3P  2  1 -1.00  0.00  2.90  2.90

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