Dear Siesta users,
Perhaps someone can help me identify if I have a problem with
understanding the Siesta basis correctly.
In my calculation of an organic molecule, using the defult siesta
basis, in the LDA approximation, I need to import the resulting
wavefunctions into my own codes for some further calculations. In
order to do this I use files:
mysystem.ascii - that contain the spherical harmonic coeffecients
c_{atm,hrm} for each atom and each harmonic (produced by readwf
routine)
as well as files (for example for Carbon atom):
ORB.S1.1.C - Rs1 radial function for s spherical harmonic
ORB.S1.2.C - Rs2 another radial function for s spherical harmonic
ORB.S2.1.C - Rp1 radial function for px, py, pz spherical harmonics
ORB.S2.2.C - Rp2 another radial function for px, py, pz spherical harmonics
ORB.S3.1.C - Rd1 radial function for dxy dyz dz^2 dxz dx^2-y^2
spherical harmonics
Where si,pi,di - are the real, cartesian representations of sp.
harmonics (for example dz^2 \propto (3z^2-r^2)/r^2)
it is was my understanding that the resulting wavefunction at a point
r, is a sum over all atoms, over all harmonics - multiplied by the
coeffecient c_{atm.htm} and the correponding radial function Ri(r).
when I look at the printout of mysystem.ascii I've the following lines:
1 H 1 1 1s
.001837530470610522 .000000000000000000
1 H 2 2 1s
.000807625106226679 .000000000000000000
1 H 3 3 1Ppy
-.000202581106039489 .000000000000000000
1 H 4 4 1Ppz
-.000051016836797005 .000000000000000000
1 H 5 5 1Ppx
.000079493143530668 .000000000000000000
.
.
.
.
85 C 421 1 2s
.000879672769932889 .000000000000000000
85 C 422 2 2s
.000696904731731352 .000000000000000000
85 C 423 3 2py
-.000947773134366972 .000000000000000000
85 C 424 4 2pz
.000721208383293865 .000000000000000000
85 C 425 5 2px
.000039515367167450 .000000000000000000
85 C 426 6 2py
-.000270531803402982 .000000000000000000
85 C 427 7 2pz
.002529969996745758 .000000000000000000
85 C 428 8 2px
.001102831954529895 .000000000000000000
85 C 429 9 2Pdxy
.000057541049761971 .000000000000000000
85 C 430 10 2Pdyz
-.000097291183540255 .000000000000000000
85 C 431 11 2Pdz2
-.000264431346561068 .000000000000000000
85 C 432 12 2Pdxz
-.000138495936294049 .000000000000000000
85 C 433 13 2Pdx2-y2
-.000305108373775229 .000000000000000000
For hydrogen siesta uses only the s and p spherical harmonics, while
for carbon as I mentioned earlier it uses s, p, d. Notice that the p
expansion coeffecients in the hydrogen are denoted as Ppy Ppz and
Ppx, while the Carbon are denoted as px py pz.
My question is if Ppy and py (and simularly px, pz) are the same
spherical harmonic functions? meaning that Ppy = py = \sqrt(3/4/pi)
y/r ?
besides this, maybe there's also something else that I need to know?
Thank you!
