Questions tagged [multi-reference]
Apply this tag to questions about methods that use multiple determinants to construct the wave function, e.g. MCSCF, MR-PT, CASSCF, MR-CI, etc., questions about chemical systems that might require these methods.
6 questions
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Why is no dynamical correlation recovered in the CASSCF method?
Configuration interaction is the only certain way to get a calculation to converge toward the exact solution of the many-body Schrödinger equation (within the approximations used for the framework of ...
- 4,773
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What exactly is meant by 'multi-configurational' and 'multireference'?
Some topics here have touched on this before (see 1, 2, 3), but I haven't found a clear definition yet.
I would like to know what exact property of the wave function these terms refer to. It would ...
- 1,459
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How does optimizing the molecular orbital coefficients in CASSCF improve its multi-reference capabilties?
The complete active space self-consistent field (CASSCF) method is a special kind of multi-configurational SCF procedure, attempting to combine Hartree-Fock (HF) and configuration interaction (CI). In ...
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What are complete active space methods and how are such spaces defined for molecules?
I am new to computational chemistry and would like to know about the active space and inactive space terminologies in MCSCF type calculations.
For understanding this I have four systems:
$\ce{H2O}$
...
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The difference between CASSCF and MCSCF methods
I'm not sure the exact difference between the MCSCF and CASSCF methods. I know that the CASSCF method proceeds by optimizing both the CSFs and MOs (I mean the coefficients), but I don't know if this ...
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What is a good (small) model system for ligand metal charge transfer practises?
I am looking for an easy to calculate model system in which I could see a ligand metal charge transfer. Basically I am looking for a model complex, that might have the metal/ligand in different ...
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