Unanswered Questions
1,264 questions with no upvoted or accepted answers
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Splitting of atomic orbitals due to Stark effect
I am performing graduate level research on ZEKE Photoelectron Spectroscopy and central to this form of spectroscopy is Rydberg states and the Stark effect. The Stark effect is caused by an electric ...
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Invisible spin allowed transitions in Tanabe-Sugano diagrams
In class we are looking at Tanabe-Sugano diagrams, more concretely at transitions for a d2 complex.
I understand that the only spin allowed transitions are those that have a triplet state, therefore ...
- 51
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Why does beryllium have an exceptionally high hydration energy?
You would expect solubility of Group $2$ fluorides to increase down the group, as lattice energy plummets much more sharply than hydration energy does. For the most part, this is true: $\ce{BaF2}$ is ...
- 750
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Wittig reagent with metal–oxo bonds
Could you use the Wittig reagent to attack a metal–oxo bond and replace the oxygen with a carbene?
Specifically, is it possible for the Wittig reagent to do σ-bond metathesis with an electrophilic ...
- 38.4k
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Stress-Strain Graph Under Uniaxial and Biaxial Strain
I was going through a recently published journal paper by ACS (Applied Nano Materials) about gas separation using nanoporous Graphene.
DOI No. - https://dx.doi.org/10.1021/acsanm.0c02340
Supporting ...
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328
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Molecular orbital diagram for carbene-metal and carbodiphosphorane-metal interaction
I am interested in understanding how carbenes and carbodiphosphoranes interact differently with a transition metals. I would like to use qualitative molecular orbital theory arguments (with an ...
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On the localized screening of cerium (when compared to iron)
I was reading the paper 'A linear response approach to the calculation of the effective interaction parameters in the LDA+U method' by Cococcioni - (Paper here) .
Quoting from the first paragraph on ...
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Is there a mistake in diagramatic representation of RS perturbation theory described in Szabo and Ostlund textbook?
I'm trying to understand rules of the diagrammatic representation of the many body perturbation theory that described in Szabo and Ostlund "Modern Quantum Chemistry" textbook. One of the ...
CommunityBot
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Interference of Ca-EDTA with fluoride delivery in mouthwash
The goal of fluoride mouthwash is to deliver $\ce{F-}$ to the surface of the teeth to turn hydroxyapatite in the dental enamel into fluorapatite.
Typically sodium fluoride or stannous fluoride are ...
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What is tetrasulfur like? Why is there so little experimental information about it?
Phys.org's How sulfur helped make Earth habitable before the rise of oxygen says
Mapping the bonds and vibrational modes of molecules containing sulfur isotopes is helping to shed light on the ...
CommunityBot
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diborane fragment orbitals energy of dihydrogen
I want to ask a question about the fragment orbitals of the $\ce{B2H6}$ system, specifically when I combine the $\ce{B2H4}$ with the $\ce{H2}$ fragments.
I am halfway through my inorganic chemistry ...
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Solubility of PbSO4
The solubility of $\ce{PbSO4(s)}$ increase with the addition of $\ce{H2SO4}.$ Why?
I don't quite understand this. When dissolving $\ce{PbSO4(s)}$ we get the equilibrium equation:
$$\ce{PbSO4(s) <=...
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What is the theoretical justification for state averaging in SA-CASSCF?
According to the molpro manual, section 7.3:
In order to compute excited states it is usually best to optimize the
energy average for all states under consideration. This avoids
root-flipping ...
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226
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How to derive a state symmetry in D2h point group from its wavefunction?
Let's have an atomic carbon with the following electron configuration:
$$
1s^2 2s^2 2p^2
$$
One of it's levels is ${}^1S_0$, which is corresponding with the following state:
$$
\begin{align}
\left| ...
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What is the magnetic moment of potassium hexacyanochromate(II)?
I calculated the magnetic moment of $\ce{K4[Cr(CN)6]}$? in the following way:
$\ce{Cr^{+2}}$ has $4$ d electrons. And since $\ce{CN-}$ is a strong field ligand, the electrons will pair up in the $\...
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