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nwchemgit / nwchem

NWChem: Open Source High-Performance Computational Chemistry
http://nwchemgit.github.io
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What is the keyword in NWCHEM to calculate reorganization energies #86

Closed xiongyan21 closed 5 years ago

xiongyan21 commented 5 years ago

Dear All Since 2016 or perhaps 2014, GAMESS has added the function to calculate reorganization energies of ET and proton-coupled ET reactions where one of the two necessary steps may fail on an old cpu in the cases of electrode plus solvent, electrode plus self assembled monolayer and solvent, electrode plus double layer and ionic solution, and homogeneous solvent, respectively, which also has an equivalent Python program. Isn't it fascinating that the electrochemical kinetic parameters can be obtained from the free energies in a solvent though quantum chemical methods, e.g., DFT, without the intricate treatment of electrodes and purification of solvents? These original programs were contributed to GAMESS by Profs. and Drs. previously in the world-wide famous Department of Chemistry of University of Illinois at Urbana-Champaign, and according to the authors' paper on SAM monolayer modified electrodes, they can produce total reorganization energies in good agreement with experimental data for all 12 metal complexes tested in aqueous solution, useful for molecular electrocatalysts electron transfer rate constants calculation. I am now enjoying it for biochemical applications in aqueous and aprotic solutions.

It is said in the NWCHEM manual that it also can calculate reorganization energies, but I cannot find any keyword or example about this. How to do it in NWCHEM? Thanks a lot!

Very Best Regards!

rangsimanketkaew commented 5 years ago

As far as I know, the current NWChem version has no module to calculate the solvent (outer-sphere) reorganization energy yet. It has only the module that calculates electron transfer matrix element called ET module.

xiongyan21 commented 5 years ago

Thanks a lot for your answer. Now I can quantum chemically get the ET rate constant from MARCUS's theory using GAMESS and NWCHEM integrately. Very Best regards！

xiongyan21 commented 5 years ago

In the QA tests, qmd_tddft exhibts only final qmd results, but qmd_tddft_h2o_svr gives the result at around every 0.24 femotoseconds elapsed. I wish to know whether it is the print level that causes different outputs of qmd_tddft and qmd_tddft_h2o_svr in the QA test. It seems that the TDDFT methods employed in NWCHEM can almost give identical results as obtained by GAMESS using a same functional without TDA for my subject compound, which is very amazing. The beginning several successive excited states chosen by me are in good agreement with the published experimental and my GAMESS cr-eomccsd(t) values, where eomccsd completely fails. I haven't tried TDA using NWCHEM for it, yet. According to my previous calculations using GAMESS for it they could fail for some functionals if TDA was used.

Thanks a lot! Very Best Regards!

xiongyan21 commented 5 years ago

MP2 6-31g(d,p) MP2 optimized hydroquinone has no warning for HESSIAN using GAMESS whose outer reorganization in anothe rsolvent is within 0.05 eV deviating from the previously mentioned article. The dftb3 optimized hydroquinoe has no warning for the HESSIAN using GAMESS, and the outer reorganization enegy in another solvent is in good agreement with that in the previously metioned article, i.e., the difference is within 0.06eV.