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### 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 $\alpha$- ...
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### 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 ...
257 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 ...
221 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 ...
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### 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 ...
164 views

### Stereoselctivity of dihydroxylation using Osmium Tetroxide

Dihydroxylation responds to steric effect and proceeds at less hindered positions. What will be the major product in the following reaction if the reagent used is $\ce{OsO4}$ followed by ...
331 views

### Is azide paramagnetic?

Is the azide ion ($\ce{N3-}$) paramagnetic? How do I use molecular orbital theory to show that it is or isn't? I drew a sine wave diagram and filled up the $1\pi$ and $2\pi$ MOs, and since there ...
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### 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 ...
427 views

### Why can't Pd/C and H2 reduce both the alkene and carbonyl portions of α,β-unsaturated carbonyls?

Why is it that the major product of the reduction of chalcones the ketone and not the monoalcohol? In other words, Why isn't the major product a benzyl alcohol? From what I understand, catalytic ...
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### Natural Bond Orbital (NBO) analyses: Physical significance/interpretation of E(2) 'stabilization energy'?

PREFACE: I am no expert on this topic. My questions at the bottom may be off base. I have some experience with symmetry-adapted perturbation theory (SAPT) when it comes to analyzing intermolecular ...
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### Why is MP2 failing to calculate proper IR frequencies for [Co(CO)4]- and [Fe(CO)4]2-?

I was doing some IR calculations on different 3d transition metal carbonyl complexes during some practical courses where we were introduced to effective core potentials. While doing this we found that ...
125 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 ...
202 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):
I tried a slightly different set up of a Galvanic cell by inserting the $\ce{Zn}$ electrode into the $\ce{CuSO4}$ solution and the $\ce{Cu}$ electrode into the $\ce{ZnSO4}$ solution. This gave a ...