Questions tagged [quantum-chemistry]
Quantum chemistry is a subfield of quantum mechanics. Like its parent field, quantum chemistry focuses on understanding physical phenomena occuring at the atomic scale. Quantum chemistry however is more focused on providing useful descriptions of electronic structure to aid in understanding chemical problems (e.g. reactions, spectra, dynamics, ...).
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Grade 12 chemistry question about Schrodinger's standing wave?
this is my first time ever using a website like this but I have something I'm curious about. My chemistry teacher showed this today (img below) and discussed how quantum of energy that hits the ...
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Difference between HOMO and LUMO and corresponding spectral gap in Hamiltonian
Coming from a Quantum Computing background, I am familiar with the singular value definition of spectral gap, I am currently trying to run Quantum Chemistry simulations and I would like to know if $|\...
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What is a degenerate orbital
I don't really get what degenerate orbitals are, I mean I know that orbitals are degenerate when they have the same energy level, and I know that the energy levels depend on n, but does that mean that ...
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Quantum Mechanics expectation value help
I am working on the following question:
I've so far done the first part of a, finding $H_{so}$ in terms of J L and S. I'm struggling to see how to relate that to $E_{LSJ}$ as it involves the ...
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Mechanism of adhesion of particles on solid surfaces [closed]
What is the mechanism of adhesion of particles on solid surfaces?
How does anything stick to anything, for that matter?
Why does cigarette smoke stay so stubbornly on our bodies?
Why does perfume also ...
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Theoretic (QED) Atomic Ionization Energies Database?
The 2019 paper "QED tests with highly-charged ions" contains a survey of QED-calculated atomic ionization energies. I can manually copy the values of interest therein, but it seem that ...
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Why does graphite have a higher standard molar entropy than diamond?
It is known that graphite (5.7 J/K mol) has a higher standard molar entropy than diamond (2.4 J/K mol) (data from Physical Chemistry by Atkins). I understand that this must be due to the structural ...
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How to compute solvent reorganization energy in Marcus' non-equilibrium approach?
I try to solve the following equations for some system solvated in the water. The goal is to obtain value in kcal/mol. Unfortunately, I cannot reach the desired output. May someone help me?
The ...
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How to display atomic charges from MOPAC calculation?
MOPAC (http://openmopac.net/) is nice semiempirical code. It also calculates charges on atoms.
Is there a free GUI to display them please ? What I know, Avogadro diplays vibrations, JMol orbitals......
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Determination of ground state energy that has the same L and S values
Determination of the energy of a multielectron atom in the ground state can be estimated using the atomic term symbol which involves the values L, S and J. If an atom has the same L and S values ...
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Can geometry of a molecule change when the spin-orbit coupling is taken into account? [closed]
Cross-posted on MMSE.
Is there any evidence that spin-orbit coupling (SOC) leads to significant changes in atomic structure? Using DFT, I am getting different relaxed lattice constants when I take SOC ...
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How to perform NBO calculations at each point while scanning the bond length?
For a given bond, I would like to perform an NBO calculation for each structure while scanning the bond lengths.
Can I use Opt=ModRedundant in combination with pop=nbo? Simply specifying both ...
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How to calculate the ground state molecular potential curve of Lithium in different spin configuration?
I am a physics student and interested in Atom, and molecule optical physics. I am studying Feshbach resonance and I need to know the potential curve of the molecule, then I ask question in physics ...
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Critical point from ab initio calculations
I was wondering if it is possible to calculate the critical point (e.g., temperature, pressure, and density) other than via experiments or equations of state like ab initio calculations.
Would anyone ...
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Mulliken Labels: How do I tell apart E, doubly degenerate, symmetry apart from T, triply degenerate, symmetry for a molecular orbital?
With A and B, it's pretty simple. If you rotate the molecule about its principle axis to where the orbitals line up, and the signs change, it's Mulliken label has a B. otherwise, it's A.
I heard E ...
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