COHP and COOP analysis from VASP
Posted: Fri Sep 20, 2013 5:50 pm
Friends of Chemical Bonding:
There seems to be some interest in a computer code which delivers chemical-bonding information (e.g., COHP or COOP plots) from plane-wave (e.g., VASP) calculations. Your wishes have been answered, the program is almost ready.
Although it is rather simple to derive Crystal Orbital Hamilton Population (COHP) analysis from local-orbital methods such as LMTO, plane waves lack locality such that one needs a little thinking to get the chemistry right. My graduate student Volker Deringer has recently shown (J. Phys. Chem. A 2011, 115, 5461) how to reconstruct COHPs from plane waves by projecting the latter onto local orbitals. Thanks, Volker! In addition, there is an analytical algorithm to project from plane-wave and PAW wavefunctions onto any suitable basis (such as the good old Slater orbitals) in order to arrive at projected COHPs, COOPs and, as a hole-in-one, accurate local densities-of-states which correctly add up to the total DOS. This approach (in press at J. Comput. Chem., doi: 10.1002/jcc.23424) is the basis of a new computer program written by another graduate student of mine, Stefan Maintz. Thanks, Stefan! My heartfelt thanks also go to Andrei Tchougr?eff who really knows about math.
In case you are interested to run the program (dubbed LOBSTER, an acronym for "Local-Orbital Basis Suite Towards Electronic-Structure Reconstruction"), please visit our freshly renovated site http://www.cohp.de and leave your contact data. LOBSTER digests VASP output and delivers chemical information. We will start shipping executables as well as the source code very soon. Try LOBSTER, it's free for academic and non-profit research!
Best wishes
Richard Dronskowski
RWTH Aachen University
There seems to be some interest in a computer code which delivers chemical-bonding information (e.g., COHP or COOP plots) from plane-wave (e.g., VASP) calculations. Your wishes have been answered, the program is almost ready.
Although it is rather simple to derive Crystal Orbital Hamilton Population (COHP) analysis from local-orbital methods such as LMTO, plane waves lack locality such that one needs a little thinking to get the chemistry right. My graduate student Volker Deringer has recently shown (J. Phys. Chem. A 2011, 115, 5461) how to reconstruct COHPs from plane waves by projecting the latter onto local orbitals. Thanks, Volker! In addition, there is an analytical algorithm to project from plane-wave and PAW wavefunctions onto any suitable basis (such as the good old Slater orbitals) in order to arrive at projected COHPs, COOPs and, as a hole-in-one, accurate local densities-of-states which correctly add up to the total DOS. This approach (in press at J. Comput. Chem., doi: 10.1002/jcc.23424) is the basis of a new computer program written by another graduate student of mine, Stefan Maintz. Thanks, Stefan! My heartfelt thanks also go to Andrei Tchougr?eff who really knows about math.
In case you are interested to run the program (dubbed LOBSTER, an acronym for "Local-Orbital Basis Suite Towards Electronic-Structure Reconstruction"), please visit our freshly renovated site http://www.cohp.de and leave your contact data. LOBSTER digests VASP output and delivers chemical information. We will start shipping executables as well as the source code very soon. Try LOBSTER, it's free for academic and non-profit research!
Best wishes
Richard Dronskowski
RWTH Aachen University