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Computational Chemistry in a Paper. Things to look at: Method: For inorganics, generally will use DFT except for extended solids
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Computational Chemistry in a Paper Things to look at: • Method: For inorganics, generally will use DFT except for extended solids • Basis Set: Generally 6-11G** on H, C, N, O and something like LANL2DZ plus polarization functions for heavy atoms (metals and P, Cl, Br, etc.). LANL2DZ contains a relativistic ccorrection • Conclusions based on small kcal/mol (maybe <5 kcal/mol) are suspect. Geometries accurate to maybe +/- 0.01 angstroms, except when comparing very similar systems qualitatively • Model compounds are often used (i.e. substitute methyl for t-Bu) to reduce computational time. Check to make sure their substitution makes sense from an electronic and steric point of view. • There's not a huge difference between Gaussian and other programs (Jaguar, etc.) as long as they're using the same methods. Gaussian is certainly the most common.
What an experiemental might look like: Computational Details: All calculations were performed with the Gaussian 03 package at the B3PW91 level of theory, with unrestricted wavefunctions used for all triplet state calculations. Basis sets used included LANL2DZ for Rh, P and Cl, 6-31G* for C and N, and 6-31G** for all hydrogens. The basis set LANL2DZ is the Los Alamos National Laboratory ECP plus a double zeta valence on Rh, P and Cl;additional d polarization functions were added to all phosphorus and chlorine atoms in all DFT calculations. All optimizations were performed with C1 symmetry and all minima were confirmed by analytical calculation of frequencies, which were also used to compute zero point energy corrections without scaling.