[Wien] charge density of a single atom
Hi I am interested in obtaining the variation in the charge density with respect to r, for isolated Y atom. For this I have seen the convergence of total energy with respect to the unit cell length, RMT*kmax and Gmax and I use a single k-point for all the calculations. I obtain 15 a.u. as the converged unit cell parameter. I have put the atom in the centre of the unit cell. scf shows that there are 11 electrons in the valence band, ie., 4s2, 4p6, 4d1, 5s2. The input for lapw2 in electron density calculation is the range of the valence electrons energy obtained in the scf file. I carry out the calculation of the 3D charge density using XCrysden, using RHO, ANG, VAL, NODEBUG as the inputs for lapw5 program. I calculate the the distribution of the charge density from the (1/2,1/2,1/2) to (1,1/2,1/2) direction along the single line to get the rho(r) versus r on a 300 point grid from the xsf data save by XCrysden. When I perform an integration of this data (by integrating the r versus 4*pi*r^2*rho(r) data) to obtain the total charge, I get ~20 electrons. I should be getting either 11 electrons, or 39 electrons, which is the atomic number of Y, what I get is neither here nor there. Can you please tell me what I am doing wrong? Is it that I have to use AIM to get the real charge density, or any other method is to be used? Regards Sharat Chandra
[Wien] charge density of a single atom
Hi I am interested in obtaining the variation in the charge density with respect to r, for isolated Y atom. For this I have seen the convergence of total energy with respect to the unit cell length, RMT*kmax and Gmax and I use a single k-point for all the calculations. I obtain 15 a.u. as the converged unit cell parameter. I have put the atom in the centre of the unit cell. scf shows that there are 11 electrons in the valence band, ie., 4s2, 4p6, 4d1, 5s2. The input for lapw2 in electron density calculation is the range of the valence electrons energy obtained in the scf file. I carry out the calculation of the 3D charge density using XCrysden, using RHO, ANG, VAL, NODEBUG as the inputs for lapw5 program. I calculate the the distribution of the charge density from the (1/2,1/2,1/2) to (1,1/2,1/2) direction along the single line to get the rho(r) versus r on a 300 point grid from the xsf data save by XCrysden. When I perform an integration of this data (by integrating the r versus 4*pi*r^2*rho(r) data) to obtain the total charge, I get ~20 electrons. I should be getting either 11 electrons, or 39 electrons, which is the atomic number of Y, what I get is neither here nor there. Can you please tell me what I am doing wrong? Is it that I have to use AIM to get the real charge density, or any other method is to be used? Regards Sharat Chandra
[Wien] charge density of a single atom
Besides the fact that a numerical integration of the 3D density on a grid will be very inaccurate, did you consider that with "ANG" you get the electron density in units of e/Ang^3, while you probably integrated over bohrs ... Am 16.05.2011 10:55, schrieb Dr. Sharat Chandra: > > Hi > > I am interested in obtaining the variation in the charge density with respect > to r, for isolated Y atom. For this I have seen the convergence of total > energy with respect to the > unit cell length, RMT*kmax and Gmax and I use a single k-point for all the > calculations. I obtain 15 a.u. as the converged unit cell parameter. I have > put the atom in the centre > of the unit cell. scf shows that there are 11 electrons in the valence band, > ie., 4s2, 4p6, 4d1, 5s2. The input for lapw2 in electron density calculation > is the range of the > valence electrons energy obtained in the scf file. I carry out the > calculation of the 3D charge density using XCrysden, using RHO, ANG, VAL, > NODEBUG as the inputs for lapw5 program. > > I calculate the the distribution of the charge density from the (1/2,1/2,1/2) > to (1,1/2,1/2) direction along the single line to get the rho(r) versus r on > a 300 point grid from > the xsf data save by XCrysden. When I perform an integration of this data (by > integrating the r versus 4*pi*r^2*rho(r) data) to obtain the total charge, I > get ~20 electrons. I > should be getting either 11 electrons, or 39 electrons, which is the atomic > number of Y, what I get is neither here nor there. > > Can you please tell me what I am doing wrong? Is it that I have to use AIM to > get the real charge density, or any other method is to be used? > > Regards > > Sharat Chandra > > > ___ > Wien mailing list > Wien at zeus.theochem.tuwien.ac.at > http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien -- P.Blaha -- Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna Phone: +43-1-58801-15671 FAX: +43-1-58801-15698 Email: blaha at theochem.tuwien.ac.atWWW: http://info.tuwien.ac.at/theochem/ --