Unanswered Questions

46
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0answers
1k views

Is there a general consensus on the causes of the alpha-effect?

There have been various explanations posited for the $\alpha$-effect. The $\alpha$-effect refers to a phenomenon wherein nucleophiles with lone pairs on atoms adjacent (i.e., in the $\alpha$- ...
17
votes
0answers
509 views

Deliquescence/efflorescence: How can I convert between salt concentration and RH?

I am looking at two phase diagrams, one has axes of $T$ and $\%\ce{MgClO4}$ in a $\ce{H2O-MgClO4}$ mix, and the other has axes of $T$ and relative humidity. The authors of the second phase diagram say ...
15
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0answers
94 views

Manuals for a Cahn TG-171 Thermogravimetric Analyzer

Recently a Cahn TG-171 Thermogravimetric Analyzer was donated to my school. We did not get a service or user's manual with it, and some of it still needs to be put back together. I have tried to ...
15
votes
0answers
220 views

How can I update a map/mesh and coordinates in a PyMol session file?

I have a PyMol session file I was using to create my figures. It contains a protein and ligand broken into several groups of atoms with a fair bit of overlap. There are also a few meshes built from ...
14
votes
0answers
133 views

Is there any experimental evidence for OClF5?

On page 88 and 89 of this document, the author laments that $\ce{OClF5}$ has still not been discovered. He says it would be "just about the ultimate possible storable oxidizer" (for rockets). (Note: ...
14
votes
0answers
162 views

Why does hyperconjugation help for ring cleavage?

The question was to rationalize it the ring cleavage happens concerted or non-concerted. The papers "The Mechanism of the Thermal Decomposition of 1-Pyrazolines and Its Relationship to ...
13
votes
0answers
268 views

Finding the number of cyclic isomers algorithmically

Is there an algorithm for finding the number of cyclic isomers a given compound might have? I've found a general algorithm for all isomers: link, but I'm not sure how to apply it for cyclic isomers ...
13
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0answers
199 views

Molecular Imaging - Any surprises to be had?

Molecular imaging, using STM and AFM technologies, appear so far to visually prove most of what we already know about chemical structures, such as VSEPR theory. For instance, here are the ideal ...
12
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0answers
163 views

Relativistic effect: d-electrons in metallorganic complexes

With higher period the d-electrons of the metal are less strong bonded and therefore oxidative addition is easier for $\ce{Ir(I)}$ than for $\ce{Rh(I)}$ and much easier than for $\ce{Co(I)}$. For ...
12
votes
0answers
98 views

When measuring avidity should you use the ligand concentration or the nanoparticle concentration?

Looking at avidity between a ligand-receptor, you're looking at an enhancement of the $K_d$ compared to a lone ligand. Is it more appropriate to compare the $K_d$ using the concentration of the ...
9
votes
0answers
67 views

How does the silver nucleate on glass in Tollen's reagent mirroring?

I'm trying to figure out how exactly does the silver start to grow during a mirroring with Tollen's reagent. I've made two pictures to illustrate how i see the nucleation/growth process of silver on ...
9
votes
0answers
88 views

Hosoya Z Index and Correlation with Boiling Point

I have recently read about the Z topological index found by Hosoya. The papers/sources The Z index is the sum of the coefficients of the matching polynomials (no. of ways to choose an independent edge ...
9
votes
1answer
111 views

What color is solid methane?

Is it blueish, perfect white or some other color? I am interested because some celestial bodies are said to be covered with methane ice.
8
votes
1answer
77 views

Are the tars in cannabis considerably more dangerous than those in tobacco?

The claim that "the tars in cannabis are considerably more dangerous than those in tobacco" is made in Patricks An Introduction to Medicinal Chemistry (4th edition, p. 169). It's just a simple one ...
8
votes
0answers
75 views

Superscript open circle notation in formula

I may be only a physicist but I'm familiar with the superscripted dot to indicate a radical. In a paper I'm reading the authors have also used a superscripted open circle. I can't find any reference ...

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