Questions tagged [psi4]
For questions about using the Psi4 Quantum Chemistry Package.
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Computing analytic derivatives of molecular Hamiltonians obtained from solving Hartree-Fock equations
I'm currently working on a quantum chemistry project, I am dealing with a second-quantized electronic Hamiltonian (corresponding to some molecule), written in terms of fermionic creation and ...
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5
votes
1
answer
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Calculating first and second derivatives of a molecular Hamiltonian?
I'm interested in computing first and second derivatives of molecular Hamiltonians with respect to nuclear coordinates. I've been using Psi4 and PySCF to perform Hartree-Fock calculations, and I was ...
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9
votes
1
answer
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Error running psi4 on charged molecules
I am running a simple energy calculation on a conformer of 3-Sulfopropyl methacrylate, which is given my C=C(C)C(=O)OCCCS(=O)(=O)[O-].
This is my workflow:
...
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8
votes
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How do I figure out how many monomer configurations I need for my simulation?
I am running a quantum mechanical simulation on Psi4 for a certain number of monomers to generate data for a database. Some of these monomers are short, while some are long.
At the moment, I am ...
- 3,897
7
votes
2
answers
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What do the indices mean in an FCIDUMP file?
I generated an FCIDUMP file, which is copied below
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1
answer
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Alternatives to VEDA 4 vibrational energy distribution analysis software?
Said software is useful when you need to assign the peaks in vibrational spectra to different vibrational modes found in a hessian calculation for a given molecule, as described in Jamróz, Michał H. “...
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18
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1
answer
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Exchange-Correlation Two-Electron Integrals
Do any freely available or proprietary electronic structure packages explicitly compute two-electron exchange correlation integrals?
I have found a few derivations to calculate excited state ...
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