135 views

### What is antisymmetric exchange? What is J-strain? Where does it come from?

I'm reading a paper1 by Sanakis, et al. that characterises the magnetic coupling in the $\ce{Fe3S4}$ clusters present in bacterial ferredoxin II and beef heart aconitase as arising through something ...
95 views

### Derivation of the Hartree-Fock equations. Functional variation

I would like to ask a question about mathematical derivation of the HF equations. Some moments related to the functional variation are not clear for me. I read a book of Szabo and Ostlund "Modern ...
84 views

### Consequences of using reagent preserved with sodium azide on gold film

I am running experiments using reagents preserved with 0.1% sodium azide, which are applied to a gold film. Unfortunately, there are very few options for using reagents without sodium azide. I ...
227 views

### Does the chemical in an alkaline battery make battery leaks unavoidable?

Battery leaks was an issue in the 80s and 90s, and since quality and innovation is constantly improving, I thought battery leak might be slowly going away. But I found that even nowadays, name brand ...
367 views

### How are turbostratic graphite phases formed?

Turbostratic graphite is graphite in which there is quenched rotational disalignment between adjacent graphene sheets, i.e. one sheet is rotated with respect to its neighbor. I suppose this could be ...
89 views

### Stoichiometric defects in ionic crystal?

The stoichiometric defects (Schottky and Frenkel defects) in ionic crystals are formed due to irregularities in ionic arrangement all the while maintaining the stoichiometry and electric neutrality. ...
203 views

### Is the nomenclature “primary”, “secondary”, “tertiary”, and “quaternary” carbon atoms limited to $sp^3$ carbon atoms?

In organic chemistry we can classify carbon atoms as primary, secondary, tertiary, or quaternary based on the number of additional carbon atoms bonded to the carbon atom of interest. The definitions ...
285 views

### What is the procedure of designing a salt bridge for a galvanic cell?

I'm doing an experiment where I'm measuring the effect of changing the $\ce{Cu^{2+}}$ ion concentration on the voltage in a copper-zinc galvanic cell. I'll be doing at least five trials for each of ...
178 views

### Reduction and re-oxidation of TiO₂

I'm having a hard time finding data about an experiment that I know has been done a bunch of times: I have a sheet of single crystal rutile $\ce{TiO_{2}}$ (110) that I want to reduce to various ...
78 views

### Difference between non-thermal and thermal ionized gases

Why or when does non-thermal plasma become thermal? How do we know before hand if the ion temperature will differ from the electron temperature, on what parameters does it depend - where is the ...
62 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 ...
168 views

### What is Cβ (C-beta) deviation?

Molprobity and some other protein structure validation tools report a Cβ deviation statistic and offer plots for it (example below). Apparently if the Cβ is greater than 0.25 Å, some ...
82 views

### What are the mechanisms for capture of As(III) and As(V) by magnetite from water?

Magnetite, $\ce{Fe3O4}$ is able to capture $\ce{As(III)}$ and $\ce{As(V)}$ from drinking water through the following mechanisms. Bidentate-binuclear complex Monodentate-binuclear complex ...