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50 views

Bonding, multiplicity and quantum chemistry for FeP$_2$

I'm trying to do some quantum chemical calculations for the linear molecule FeP$_2$ in the gas phase as well as its crystal (orthorhombic symmetry like here). I am lead to believe that in both cases ...
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2answers
93 views

Is a diamond a single molecule?

Assuming a perfect diamond with no impurities. Would this diamond considered to be a single large molecule? Browsing the interweb I found several opinions about this but did not find a clear Yes or ...
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1answer
101 views

is there any mnemonic for the AXE method?

Is there any mnemonic that helps remembering the names of the different geometries (Shapes) that we obtain from applying the AXE method ?
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2answers
60 views

Is it possible to cut yourself on pyrite?

I am planning an RPG adventure where the characters might end up getting a large cubic lump of "gold", which in reality, as you might have guessed, is in fact pyrite. I also wanted to plan for the ...
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2answers
84 views

Why does ZnO turn yellow when it is hot?

Why does ZnO's color become yellow when it is hot? I have read that it is because of physical properties, but I need a more elaborate explanation.
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0answers
81 views

How do you determine a chemical formula given the molecule's crystal structure?

How do you determine the chemical formula of a compound given its crystal structure?
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180 views

How to calculate lattice parameter only using planes and d spacing

I am trying to find lattice parameter of a hexagonal crystal, usually i uses cellcalc for calculating lattice parameter of a crystal struture. In that software it asks only two queries one is details ...
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1answer
14 views

What conditions to use to crystallise Equine Myoglobin?

What are the crystallisation conditions for Equine Myoglobin? I've tried repeating some from the PDB but no success.
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1answer
52 views

Relating a compound's radii and unit cell dimensions

We're asked often to calculate the density of a crystal, and there is a known formula for that related to the unit cell volume. Now, for simple geometric structures such as the bcc structure (and ...
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2answers
4k views

How to calculate crystal field stabilisation energy?

How to calculate it? I know that it depends on the coordination compound and the number of electrons present in t2g and eg orbitals and the final answer is expressed in terms of crystal field ...
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1answer
56 views

Liquid crystal current flow

Sorry, maybe some terms used in the question are not correct and may be this is a trivial question, but I'm not a chemist I am a computer scientist. In a liquid crystal cell used for LCD the ...
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1answer
201 views

Use of Sulphuric Acid in Crystallization

I read that:- Take a cupful of water in a beaker and add a few drops of dilute sulphuric acid. Heat the water. When it starts boiling add copper sulphate powder slowly while stirring ...
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1answer
359 views

Effect of dopant size on XRD peak shift

If we add an impurity atom (doping) to the crystalline struture of another material and take the XRD of the doped material what kind of peak shift can we expect. For the better description of my ...
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3answers
92 views

Which gems can be prepared on a small scale basis?

I am interested to know the following: Which gems can be prepared at home(without sophisticated instruments) ? What will be the quality(appearance) of the product for a certain method ? I want ...
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1answer
640 views

Confusion in unit cells of crystal system

Unit cells are divided into two main types Primitive Non-primitive Primitive includes simple cubic lattice whereas non-primitive includes fcc bcc end centered.. Among the seven types of crystal ...
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1answer
105 views

Crystallization of solutions and liquids

The process of crystallization of a liquid or any solute occurs when its concentration exceeds the maximum concentration which the solvent can carry or when the temperature drops below the freezing ...
3
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1answer
84 views

Help Identifying Chemicals

I was trying to isolate elemental bismuth from pepto bismol (bismuth subsalicylate) using the process seen here but after I added the HCl, instead of getting a pink foamy substance I got a white ...
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1answer
215 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 ...
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1answer
1k views

Which theta should be taken from xrd pattern for calculating Scherrer's equation

We use scherrer's equation to calculate crystalline size of a particle. But which theta should we take from xrd pattern for this calculation. For example Above picture shows the diffraction ...
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1answer
40 views

How are crystals formed from a gas?

In crystallization, crystals are formed from liquids by cooling. How can crystals be formed from a gas by cooling?
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313 views

What is burst nucleation?

Can you tell me what is a burst nucleation process, and how can it be used for synthesising uniform nanoparticles? Can you also provide (if possible) any links to papers or materials regarding ...
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1answer
228 views

Why are there no edge dislocations in a face-centered cubic (FCC) lattice?

In crystallography, we know that the Burgers vector is parallel to the dislocation direction in a screw dislocation, and perpendicular in a edge dislocation. Furthermore, I have in my lecture notes ...
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257 views

How is the electron “trapped in the crystal” in irradiated NaCl?

Pennsylvania State University provides irradiated NaCl (180,000 rads of gamma radiation) to teachers for a very entertaining demonstration. The salt is orange after irradiation. When it is placed on a ...