Messages

31

General Questions and Answers / Re: question in the new version

« on: July 9, 2010, 08:42 »

Ok, thank you! My PC is 4 cores Windows XP operating system, now I just want to run the job in parallel, but it seems that there are some issues, I can not realize it. whether are there any introductions about the parallel calculation on windows XP? thanks!

32

General Questions and Answers / question in the new version

« on: July 8, 2010, 03:56 »

Dear everyone,
    1)In the new version, it seems that the electrodes formations are always changed with the changes of electrode copy length, and the left and right periodic lead parts are not same like 2008.10, how do understand it.
    2) If I want to run the job in parallel on Windows XP(one machine with 4 CPUs), whether I need to install the mpich2, and how to assgin the CPUs(just now I use the trial license, does it support the parallel)
   Thank you!

33

General Questions and Answers / some questions about MO

« on: May 17, 2010, 07:08 »

Dear everyone,

      when calculating the spin transport properties of one magnetic  molecule, the MPSH energy spectrum is list
# -----------------------------------------------------------------------------
# Energy Spectrum
# -----------------------------------------------------------------------------
# Spin-Up Energy (eV)  Spin-Down Energy (eV)
               -18.49                 -18.51
               -17.76                 -17.76
               -17.31                 -17.31
-----------------------------------------
                -1.94                  -0.79
                -1.83                  -0.50
                -1.36                  -0.40
                -1.32                   0.02
                -0.01                  1.24
                 0.02                  1.49
                 1.75                   1.92
------------------------------------------
I have some questions that:

(1) Is the Fermi level same for spin up state and spin down state(E_fermi=0?)
(2) Now, how can we decide the quantum numebers to calculate the MPSH HOMO and LUMO, here, for spin up state, the energy -0.01 and 0.02 correspond to HOMO and LUMO, respectively, and for spin down state -0.40 and 0.02 correspond to HOMO and LUMO? Is it alway right?
(3)Due to the smearing effect, whether the Fermi level could be brodened, and results -0.01 and 0.02 could be treated as 0. if so, sometimes it could be difficult to accurately judge the quantum number of HOMO and LUMO, even due to annexation of energy level.   Now, whether it is effective to judge it according to the different spin stats electron occupation.
(4) Usually, whether are there any obvious differences between the spatial distribution of HOMO or LUMO of one isolated molecule   and that of its MPSH MOs when coulped into two electrodes?

thank you!