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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Why are there only 14 types of Bravais lattices and not 28 when there are 7 types of unit cells and each can have four variations?
As the title suggests, I can't understand why certain kinds of variations (like Face-centred or Body-centred) are restricted to certain types of unit cells. An orthorhombic unit cell has Primitive, ...
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Of 2-bromobutan-2-ol and trans-1,2-dimethylcyclobutane which is chiral as well as dissymmetric?
In an examination I was asked to determine the molecules which are chiral as well as dissymmetric. There were four options, and among them, two were achiral, as they had an improper axis of symmetry. ...
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Planes of symmetry of a molecule
Are we limited to use only xy, yz and zx planes to check for planes of symmetry of a molecule? Because I see a plane of symmetry in the following molecule through the two shown H atoms or OH groups. ...
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Solution of the Roothaan Equations of H2 by Symmetry Arguments
FWIW my background is in physics and maths, but I am just starting a chemistry PhD (the last time I took a chemistry class was high school). I have only some background in representation theory, and ...
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Why does twistronic 'magic angle' graphene have only 180-degree symmetry?
From Graphene superconductors may be less exotic than physicists hoped[1]:
Excitement rose earlier this year with the discovery of
superconductivity in a similar
system[2]:
three layers of graphene ...
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Analysis of metal carbonyl bonding in Fe(CO)5 using molecular orbitals
I am really struggling with this question we have been set in class:
Metal-carbonyl bonding: Conceptionally, one can build up $\ce{[Fe(CO)5]}$ from the $\ce{Fe(CO)4}$ fragment plus free $\ce{CO}$ in ...
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Why does an improper rotation axis preclude chirality?
Can anybody prove that any molecule with an axis of improper rotation is nonchiral? I still do not understand why this is so, any proper mathematical proof or visualisation of a generalised molecule ...
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d orbital irreducible representations in metal in ML4 model [closed]
In ML4 (Metal—4 ligands)model which has a square planar shape and D4h point group, what is the irreducible representation for the 5 kinds of d orbitals in the central metal?
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Using symmetry and group theory arguments to explain iron(II) in a tetrahedral crystal field
I am trying to figure out how to explain $1s \rightarrow 3d$ spectroscopic transitions for $\ce{Fe^{2+}}$ in $T_\mathrm{d}$ symmetry. These transitions make up the pre-edge region in K edge X-ray ...
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High symmetry points and x-coordinates
Is it possible to work out the x-coordinates related to high symmetry points?
The software I'm using doesn't provide me with that, so I was wondering if there is a way to manually figure it out, as I ...
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Symmetry representations for acetonitrile (CH3CN)
Can anybody share the symmetry labels for acetonitrile ($\ce{CH3CN}$), please?
I mean to assign the symmetry labels to orbitals of acetonitrile
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Is there a geometrically intuitive explanation of the equivalence of the numbers of irreducible representations and symmetry classes?
In group theory, as used in chemistry, we’re familiar with the idea that the number of irreducible representations of a symmetry group equals the number of classes of symmetry operations, e.g. three ...
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Is there any mathematical or logical proof that carbon with 4 different groups would be chiral?
In chemistry; chirality is generally defined in 2 ways.
Lord Kelvin's definition: "I call any geometrical figure, or group of points, chiral, and say it has chirality, if its image in a plane ...
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Why does hydrogenation of this compound not result in a diastereomeric mixture? [duplicate]
In a question, this compound was given and it was asked:
"Hydrogenation of the above compound in the presence of poisoned Palladium catalyst gives?"
When I was answering it, I thought that ...
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Why is the base-centered orthorhombic crystal lattice a unique crystal system?
I'm having difficulty understanding why the base-centered orthorhombic crystal system is a unique crystal system. When I draw two base-centered orthorhombic unit cells next to each other there appears ...
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