Questions tagged [symmetry]
The description of the symmetry present in molecules. Molecular symmetry is useful for explaining or predicting of a molecule's chemical properties.
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Amplitudes and phases of transform of an image
I have recorded an image of a large macromolecule and after several types of image analysis, have obtained a rotationally averaged image, that is not quite perfect, but appears to show 6-fold symmetry....
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Does symmetry lower the energy of molecules?
Why does nature "prefer" symmetry? Why is symmetry energy-lowering? I keep hearing statements along the lines of this tossed around by chemists. Here are some examples:
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Equivalent points for 3 fold and 6 fold symmetry
In a crystal Lattice how to find the equivalent points for 3 fold and 6 fold symmetry?
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Why does symmetry have to be maintained in molecular orbitals?
Using the example of $\ce{XeF4}$:
What is the physical explanation enforcing the symmetry of the $\ce{1b_{1g}}$ orbital on the fluorine atoms? Why isn't the symmetry of a nonbonding orbital arbitrary?...
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When is it true that more nodes equals higher energy?
Consider all the MOs of some isolated molecule. (It could be a single
atom too; I'll use MO to refer to AOs as well.) Number them in
increasing order of the number of nodes (node = surface where the ...
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Accessible statement on the intuition and usefulness of group theory to chemistry
I am writing a lesson plan for high school students who are studying group theory,
and I am having difficulty in relating the subject matter to the real world.
I have quite a few examples using the ...
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How does one recognized Td/Oh symmetry in molecules?
The identification of point groups of a molecule is usually done following a strict scheme, either manually or algorithmically. In all textbooks I could find, however, the first step of the scheme is ...
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How do I determine the crystal field splitting for an arbitrary point group?
How can I figure out the degeneracy of the d orbitals for a site that has a given point group? Specifically I'm interested in $D_{3d}$ and $D_{3h}$, but it would be good to know how to do it in the ...
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Determining the lowest rank non-vanishing multipole moment [closed]
I have been told that the multipole moments of rank 0,1,2,3,...n have respectively 1,3,5,7,...2n+1 components which transform like the spherical harmonics of rank 0,1,2,3,...n. How do I use the ...
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An example to illustrate the difference between an inversion operation and a twofold rotation
Reading in Atkin's Inorganic Chemistry book, I cam accross:
Although an inversion and a twofold rotation may sometimes achieve the
same effect, that is not the case in general and the two ...
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Are these two space groups in a group–subgroup relationship?
Given two crystal space groups, how can one determine if they are in a group-subgroup relationship? The specific case at hand is P 21/m 2/m 2/a (aka P m m a, #51) and P m m 2 (#25), but knowing how to ...
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Are all cubic point groups encountered?
My symmetry lecture notes state that there are seven high-symmetry 3D point groups, which have more than one rotation axis of order greater than 2: $T$, $T_d$, $T_h$, $O$, $O_h$, $I$, $I_h$. I ...
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Is a 2-D periodic structure isomorphic with the surface of a torus, a sphere, neither or both?
When I was reading through the ADF-BAND tutorials, one of the toy systems presented was a 1-D periodic structure involving 3 collinear hydrogen atoms. The tutorial pointed out that, topologically ...
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