Unanswered Questions

26
votes
0answers
746 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 $\alpha$- ...
13
votes
0answers
168 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 ...
11
votes
0answers
262 views

Why does depurination happen at a higher pH (or under less harsh conditions) than depyrimidation?

I've always wondered why the N-glycosidic bond, which connects the adenine or guanine purine bases to their sugars, was the easiest to cleave via acid hydrolysis, or why purines have the lowest ...
8
votes
0answers
58 views

What would follow in the series sigma, pi and delta bonds?

I realise, that this question is a stretch, but I was wondering, how would a bonding orbital be called if it was formed from two $f_{x(x^2−3y^2)}$ or $f_{y(3x^2−y^2)}$ orbitals. Have there been any ...
8
votes
0answers
237 views

Influence of Temperature on Biochemical Reactions

Short question How (quantitatively speaking) does temperature influences rate of decay of proteins? I am looking for some general number/function, the influence of temperature on an average protein. ...
8
votes
0answers
70 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 ...
8
votes
0answers
133 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: http://www-jmg.ch.cam.ac.uk/data/isomercount/isojava.html, ...
8
votes
0answers
74 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 ...
7
votes
0answers
134 views

Mechanism of dehydrogenation with Nosylate

What is the mechanism of the attached reaction? How could nosylate do the dehydrogenation? The reaction is from this synthesis (46th IChO preparatory problem 26):
7
votes
0answers
149 views

Is hybridization used in ab-initio valance bond calculation?

Many general chemistry textbooks introduced the concept "hybridization" to construct a symmetry-adapted VB-type wavefunction. In the textbooks, usually the minimal basis is used and without optimizing ...
7
votes
0answers
131 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 ...
7
votes
0answers
410 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 ...
6
votes
0answers
37 views

How does epoxy stick to stuff?

According to Wikipedia what gives epoxy it's holding power is apparently "ionic" interactions between the epoxy and the surface. But I thought that epoxy was overall neutral when cured. How can it ...
6
votes
1answer
72 views

How to express uncertainty containing values with error progression?

A student reported the mass of 10 glass beads as $2.507 \pm 0.015~\mathrm{g}$. What should the student report as the mass of one bead? A student reported the density of ten glass beads as ...
6
votes
0answers
49 views

How to get defect-energy level diagram from PL data

I am reading this article Phys. Chem. Chem. Phys. , 2011, 13, 14902-14905 and seen that the authors have drawn a image of defect level using PL data Can you explain me how this diagram can be drawn ...

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