All Questions
Tagged with symmetry molecular-structure
22
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When does the angle between the planes in tetrahedral molecule with central atom deviate from 90°?
Consider an atom X bonded to four other atoms A, B, C, D in a tetrahedral fashion with sp³ hybridisation. If A, B, C, D are the same, every bond angle is 109.47°, and the angle between the planes ...
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Reading Stereographs
On an old paper, I found an interesting representation of some symmetry operations: stereographs.
Online I found a set of symmetry operations and related stereographs (see: http://newton.ex.ac.uk/...
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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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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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How are there two C3 rotation axes in ammonia?
If we look at the character table for the $C_\mathrm{3v}$ point group (which $\ce{NH3}$ is an example of), we see that these are the symmetry elements ${E, 2 C_3, 3 \sigma_v}$ present in the molecule. ...
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$Q_3$ is symmetric with respect to the $\sigma_v$ operation?
I am currently studying the textbook Infrared and Raman Spectroscopy: Principles and Spectral Interpretation, second edition, by Peter J. Larkin. Section 8. Symmetry: Infrared and Raman Active ...
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4
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Do we consider the spatial orientation of a molecular orbital while assigning plane of symmetry?
I am following the video lectures by Neeraj Saini sir and in this video$^{\dagger}$ he said that $\ce{CO2}$ has infinite planes of symmetry.
But I think that if we take into account the orientation of ...
CommunityBot
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7
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In what way trans alkenes are more symmetric than cis alkenes?
While providing the reason for the higher melting point of trans molecules, everyone says that trans molecules are more symmetric than cis molecules. An example can be found over here, where the OP ...
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1
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1
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Determine and draw planes and axes of symmetry of a molecule using software (VESTA or Mercury)
I designed the $\text{MoS}_2$ molecule (bilayer), with polytype 2H in the VESTA. My goal is to draw the plans and axes of symmetry of the bilayer set. According to the information in the literature, ...
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Are there optically active molecules in which all atoms lie in the same plane?
I've learnt that when a molecule is non-superposable on its mirror image, it exists as a pair of enantiomers and is optically active. Absence of plane of symmetry is given to be one of the properties ...
- 71.6k
6
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2
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Chromium cyanide complexes
I have rarely seen any chromium $(\ce{Cr})$ square planar complexes and I have been told that $\ce{[Cr(CN)4]-}$ is tetrahedral.
So, if the statement is actually correct, are there any other known ...
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3
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1
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Number of stereoisomers of polysubstituted cubane
The molecule given below is a substituted cubane.
a) How many stereoisomers exist for this molecule?
b) How many pairs of enantiomers are possible?
How do I calculate the number of stereoisomers? ...
CommunityBot
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2
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2
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Dipole moment of symmetrical molecules
While studying dipole moment in organic chemistry, I got stuck at a particular statement written in the book :
Symmetrical molecules without lone pairs of electrons will have $\mu = 0.$
The main ...
- 71.6k
3
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1
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AB5E type molecule
In $\ce{AB5E}$-type molecules, why are the lone pairs in axial bonds?
If the lone pair is present in axial bonds it repels four other bonds. On the other hand if the lone pair is in equatorial ...
- 38.4k
6
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Why doesn't 1,3-dichloro-2,4-dimethylcyclobutane have a plane of symmetry?
In (1R,2R,3S,4S)-1,3-dichloro-2,4-dimethylcyclobutane, are the blue lines not planes of symmetry?
My book says it has a centre of symmetry, but not a plane of symmetry. But if I took a cut ...
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