Questions tagged [atomic-physics]
Questions about atomic physics.
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Why are some point groups for single atoms listed as Oh in the CCCBDB?
Does anyone know why the CCCBDB database lists the tin cation and antimony atom as having the Oh point group (please see the screenshot below from CCCBDB when I look at "All molecules sorted by ...
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How to find out electric field Intensity for a far distant point in COMSOL multi Physics
I have a surface plot for which I would like to find the E (Electric field intensity) at a far field point marked in red on the plot.
Therefore I would like to calculate Ex and Ey, so that I can ...
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Primitive Translation Vectors from Lattice Vectors (with varying Space Groups)
I am looking at some raw POSCAR data of some Primitive Cells, and I wonder how I can get a simplified directional representation of the lattice vectors. I have two examples:
Example 1:
...
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Finding the Configuration State Functions of Atoms
Is there a book or tabulated work where the configuration state functions of atoms have been documented? Just as useful would be information about computer programs that are able to predict the CSFs.
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Gaussian(Software): What does atomic orbital contribution mean?
Example Molecule: C60 (Fullerene)
Route Section: #p B3LYP/6-311G(d) guess = read geom = check pop = full
Question: What information can I get from atomic orbital contributions?
I've calculated atomic ...
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Why can't DFT calculate the accurate electronic configuration of the Oxygen atom?
I am trying to do a DFT calculation of Oxygen atoms with the VASP code. My settings follow the official tutorial on the Oxygen atom of VASP. But it turns out the energy levels of the two spin ...
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In which theoretical framework does the size of an atom depend on the temperature of the gas (Bose-Einstein condensates)
In order to pose the question, I reproduce an excerpt from this Physics.SE question, about the size of atoms in a Bose-Einstein condensate (BEC):
Heisenberg's uncertainty principle in frames of ...
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How to determine which levels correspond to each other in LS coupling and jj-coupling?
In the LS coupling scheme, L, S and J are good quantum numbers; whereas in jj-coupling scheme, j1, j2 and J are good quantum numbers. I have learnt how to get the term symbols for LS coupling, and for ...
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Atomic Packing Fraction [closed]
I need to calculate excess entropy of mixing for a particular system of alloy. The excess entropy of mixing is dependent on temperature and it takes into account this temperature dependence by using ...
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Quantifying electronic overlap?
I am trying to understand how to quantify the electronic interaction/conduction/overlap between two metal cores at varying distances. As someone who works primarily with classical MD, and has less ...
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High precision helium energy
In the paper "High Precision Theory of Atomic Helium", Drake lists the then best-known ground state energy of the Schrödinger equation for helium to 22 digits as:
$$\lambda_0 \approx -2....
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How accurate are the most accurate calculations?
Taking into account the fact that the theory of quantum gravity does not exist and the QED calculations are not possible for most realistic chemical systems, what levels of accuracy can we expect from ...
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