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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Does this set of quantum numbers have a unique solution?
I received the following question:
Complete the missing values for the four quantum numbers:
$n=?$, $\ell = 2 , m_\ell = 0$ , $m_s= ? $ .
The problem is that I think $n$ can be any number ...
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What is the 'ancestral term' in the LS coupling scheme?
On the physics.nist.gov site: http://physics.nist.gov/Pubs/AtSpec/node06.html
The table titled "Atomic structural hierarchy in LS coupling and names for the groups of all transitions between ...
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multielectron spin-orbit coupling and energy level
For multi-electron atoms for which the Hamiltonian (including the spin-orbit coupling) reads
$$H=\sum_i T_i-Z\sum_i V_i+\sum_i V_i^{\text{s.o.}}+\sum_{i>j}V_{ij}$$
The $T_i$ are the kinetic ...
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Moment of inertia for a triatomic molecule
What does the moment of inertia for a molecule mean? How is it useful? Most importantly, how would I go about solving it for a triatomic molecule?
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Modeling perturbations of a quantum mechanical system
I'm wondering how to properly perturb a quantum mechanical system.
I'm looking for a way to express the return to equilibrium of such a perturbed state, where the perturbation is in the Hamiltonian. ...
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Is the Springborg 6D phase space model used in modern molecular orbital modeling?
In various papers written in the 1980s, Michael Springborg explored an interpretation of the Wigner phase space function as an electron density in a six-dimensional $(q,p)$ phase space. He applied it ...
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Has QTPIE ever been applied to 1D metals such as polyacetylene?
QTPIE is a fluctuating charge model that substantially improves modeling of polarization and charge transfer. I was curious whether it has ever been applied to 1D metals such as polyacetylene to ...
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Pauli exclusion principle and resonance
I've always been a bit uncomfortable with the concept of more than two electrons in a single orbital-like region(probability-wise) which occurs in resonance.
This seems to disobey Pauli's exclusion ...
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Symmetry lost in orbitals?
I've always thought that orbitals lead to a loss of symmetry, and have never been able to give myself a satisfactory answer to this.
I'll explain via an example:
Let's take an $\ce{N^3+}$ atom. It's ...
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Non-integer hybridization
I've known that hybridization in distorted geometries is not exactly $sp^3$ or $sp^2$ or whatever. For example, $\ce{PH3}$ has nearly pure $p$ orbitals in the $\ce{P-H}$ bond, and the lone pair is in ...
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Why is the 2s orbital lower in energy than the 2p orbital when the electrons in 2s are usually farther from the nucleus?
My chemistry book explains that even though electrons in the $\mathrm{2p}$ orbital are closer to the nucleus on average, electrons from the $\mathrm{2s}$ orbital spend a very short time very close to ...
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