Spin Orbital Calculations

These notes detail how to invoke and run the MAG set of codes from the Kaupp group.

Run a Gaussian calculation using the following keywords

# uB3LYP/aug-cc-pvdz fchk=(mo,basis) IOP(3/32=2) Field=F(18)10 scf(tight)

Note that use of the Pople (6-31G(d,p) basis sets, with shared exponents, is not programmed into MAG. One recommendation is to use IGLO-II (double ζ) or IGLO-III (triple ζ), but we think that the cc-pvdz is also fine. The B3LYP DFT hybrid is directly programmed into MAG; they recommend BP86 instead, but in our hands this does tend to give less good results (it may be faster to run however). The keyword Field=F(18)10 relates to computing the SO correction for eg atom 18 (in the order specified in the input file), which would normally be eg a ¹³C although it might also be hydrogen. The factor of 10 is adjustable (being a perturbation). Higher or lower values could be tried to see if it makes much difference.

Recover the following three files

The fcck file (best obtained by actually running the job in the uportal, which generates it automatically, the .out or .log file, and the .gjf input file.

Transfer to a computer implementing the MAG codes

currently, this is armstrong.ch.ic.ac.uk but a better location might be found in the future.

Run the GS2RS-scan script as follows

./GS2RS-scan Ferr_bp86_SO_1 where Ferr_bp86_SO_1 is the prefix to the .fchk file (i.e. the name of the job). This will not take more than a few minutes, and will generate intermediate files for the next step.

Run the RUN_MAG script as follows

./RUN_MAG Cr1_bp86_SO_21 gZ-FULL where Cr1_bp86_SO_21 is the same prefix as before, and gZ-FULL refers to a separate job definition file called gZ-FULL.M residing in the same directory, and which specifies what kind of calculation is requested. Probably not needed to change this much.

The output file

is located in a file of name prefix.OUT_gZ-FULL and it takes the form

SL-CORRECTION FOR NUCLEUS (# 10) = 5.84

The calculation may take several hours to run.