Unanswered Questions
205 questions with no upvoted or accepted answers
10
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Frontier orbital analysis of zinc-catalysed carbonyl-ene reaction
Q1. Is the $\sigma_\ce{C-H}$ bond a donor in this reaction? If not, then can we take the alternate combination (HOMO of alkene, LUMO of the $\ce{C-H}$ bond and, HOMO of the carbonyl)?
Q2. We can also ...
CommunityBot
- 1
10
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0
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1k
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Orbital and state correlation diagram for ring-closure of pentadienyl to a cyclic allyl
This is an exam question. I am to construct the orbital and state correlation diagram for one of the reaction below (disrotation or conratation). Also, I should explain whether the reaction is ...
- 41.2k
9
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0
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196
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Is there a reliable chemical theory that predicts pKa based on structure?
Obviously, there are general stability arguments that can be made to estimate relative pKas, such as evaluating the stability of the conjugate base of an acid, or thinking about how polarized the bond ...
- 38.4k
9
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0
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898
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Free Web-Based Orbital Solver to look into the Walsh orbitals of a perturbed cyclopropane
There exists a free online orbital calculator.
When I draw cyclopropane it plots three molecular orbitals, but unfortunately it doesn't use the Walsh orbitals.
Are there any free online tools which ...
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8
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0
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266
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Why is octaoxygen diamagnetic?
I tried considering that according to LCAO-MO theory $\ce{O2}$ is paramagnetic, which is confirmed by experimental evidence. Since octaoxygen has the crystal structure in figure, I thought there is a ...
- 189
8
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599
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Bond orders in the 3c-4e bond and 3c-2e bond
According to D. P. M. Mingos, in his book Essential Trends in Inorganic Chemistry, the bond order of the three-centre four-electron bond is approximately 0.717, which is one divided by the square root ...
- 10.7k
7
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Is the 9H-fluoren-9-ylium cation aromatic?
In this cation, there are two individual benzene rings which are aromatic. But in the entire π system, there are 12 π-electrons which should make it antiromatic. Which is correct?
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7
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881
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Chemical bonding with f orbitals
For the elements such as rhenium, osmium, iridium how probable is for electrons in the inner 4f orbitals to gain energy and take part in a molecular orbital (such as an $f^2 d^2 s p^3$ hybrid orbital) ...
- 10.7k
6
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451
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How to explain oxidizing power from Molecular Orbital Theory
I am trying to explain the oxidizing property of $\ce{Fe^3+}$ in $\ce{H2O}$ and $\ce{CN^-}$ which is $\ce{[Fe(H2O)6]^3+}$ and $\ce{[Fe(CN)6]^3-}$.
The electrochemical reactions along with their ...
CommunityBot
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6
votes
0
answers
78
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Why SCF-MO methods fail when treating bond-breaking processes?
I'm currently studying the EVB(Empirical Valence Bond) approach. While reading on this article (https://pubs.acs.org/doi/10.1021/ja00224a011), the author mentioned about the usage of SCF-MO formalism ...
- 221
6
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141
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How do bonds rotate in pericyclic reactions?
In Pericyclic reactions, it is shown that the terminal bonds rotate (conrotation or disrotation) to allow for allignment of the FMO's, thereby forming the sigma bond
However, a detail that most of my ...
- 6,278
6
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0
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191
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Is any symmetry element conserved during a supra-antarafacial cyclo addition of two cis-butadiene units
I tried to construct a correlation diagram for the [4+4] cyclo addition of two cis-butadiene units. But I failed to construct any meaning full orbitals for the "educt" side where the two butadiene ...
- 1,245
6
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0
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972
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Platt's Notation/Nomenclature for transitions
How do you read Platt's Notation / Nomenclature? Where can I learn this?
Some examples where I've seen this mentioned:
In Platt's notation the transitions are designated as $\ce{A -> B}$ and $\ce{...
- 1
5
votes
0
answers
608
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Explanation of the trans-effect (thermodynamic and kinetic) for octahedral transition metal complexes
The thermodynamic trans effect refers to the ground state weakening of the metal-ligand bond in a complex by a ligand trans to it. The kinetic trans effect is the lablisation of a ligand in a complex ...
- 5,685
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441
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Orbital Interaction for electrophile and nucleophile
Clearly, the above diagrams depict the interaction between empty orbital of electrophile with filled orbital of nucleophile. We may assume that the HOMO of nucleophile being more electronegative will ...
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