In mineralogy and crystallography, a crystal structure is a unique arrangement of atoms or molecules in a crystalline liquid or solid.

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How would one construct a 3D model of a molecule based on the crystal structure of its salts?

Often crystal structures found online from past published crystallography experiments are of the salt of a molecule of biologic interest, as opposed to the freebase form of the molecule itself. For ...
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What things form crystals? [on hold]

Just getting interested in this stuff. People are saying I should crystallize salt, for example. What things could I do instead of salt with and still get a crystal from? Thanks a ton!!
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Crystal field theory for calculating lattice parameters

If I have an 8-coordinated metal cation (e.g., $\ce{Te}$, $\ce{Nb}$, $\ce{Ta}$, $\ce{Sb}$, $\ce{Bi}$, $\ce{Zr}$, $\ce{Hf}$) by oxygen anions, is there a way to theoretically calculate the structure of ...
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Can bone mineral be obtained in pure, crystalline form?

Can bone mineral be obtained in pure, crystalline form outside a living organism? Had this been done ever?
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Structure of Ca2B6O11

What is its structure? I found an image of B6O11 unit but it looks incorrect: The top left corner one. The oxygen can make max 2 bonds but O8 has three! There are six oxygen with ...
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How to determine the Bravais lattice and atom basis vectors from a CIF file?

Say I have a CIF file describing some material in terms of its symmetry space group, lattice parameters and in-cell atom positions. A simple example might be, ...
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Modified DNA bases in Pymol and Coot

When using Pymol or Coot molecular visualization software to solve x-ray crystallography structures, how can I mutate a cytosine to a 5-methylcytosine?
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Theoretical Calculation of Lattice Parameter from Space Group

If I am given a compound which belongs to, say the cubic $\text{Ia}\bar 3\text{d}$ space group, is there a known way to calculate the lattice parameter of the compound? In general, can lattice ...
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How to predict if hydrogen atoms could be placed in the interstials of a lattice

Palladium hydride is an example of a hydride which contains H atoms in palladium's crystal lattice (which is fcc). I would like to know if it's possible to predict if another hydride, $\ce{NbH_{x}}$ ...
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Determining structure factors for crystals from lattice and motif

I understand that the structure factor for a crystal is given by: $F_{hkl} = \displaystyle\sum_r f_{r} e^{2{\pi}i(hx_{r}+ky_{r}+lz_{r})} $ My textbook (''Structures of crystals'', Glazier) ...
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Why is sand/glass polar? How does lattice structure change polarity?

The molecular geometry of sand is linear. Dipole moment is thus cancelled. But we all know from the meniscus water makes with glass that the dipole-dipole/H-O attraction between sand and water is ...
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Can chemicals change crystal structure by only touching?

Are there any known, or suspected compounds that take the crystal structure of what ever object they are touching, i.e. if it touches $\ce{NaCl}$ it would turn into a face centered cubic crystal ...
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Is there any required data missing from my CIF file?

I previously asked a question about a CIF file here (namely CIF fields that are available for some atoms, but not others) I think I have the answer (namely to place dots [.] at places where the two ...
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CIF fields that are available for some atoms, but not others

I've been working on another CIF file, this time for (-)-threo-methylphenidate based on Pharma Res, 1995 (sadly the relevant crystallography data isn't supplied in the free preview at Springer). I ...
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Azathioprine CIF data file rendering problem in Accelrys

I have been working on a CIF data file (URL: http://goo.gl/2cprI6) based on data from this experiment: Acharya, 1984 (free full text isn't available, but the page [page 2] with the experiment details ...
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Macroscopic features of a transition metal with a cubic closed packed structure [duplicate]

How would a transition metal with a cubic closed packed structure affect macroscopic features of that solid? I'm also not sure what it means by macroscopic features?
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How does the atomic structure of crystals determines its shapes? [duplicate]

for example, table salt has an a cubic structure in the atomic level, and they are often cube like in the visible level. I don't see any reason that the atomic crystal structure should reflect the ...
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Why does pyrite form cubic crystals?

Pyrite ($\ce{FeS2}$) forms cubic crystals, like these ones: I know that the crystal structure is primitive cubic, but I don’t see how cubic structure on the molecular level translates to cubic ...
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When does hydrogen bonding happen?

What kinds of molecules will experience hydrogen bonding (inter and intra)? Why does it occur for some H atoms but not others?
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What is a catemer?

What is a catemer and how does it differ from a dimer? What type of compounds could form catemers and how does their formation influence its crystal structure?
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Coloration of substances because of F-Centers

In case of metal deficient defects in the crystal lattice of a metal, the positive voids are filled by electrons. How does this result in the coloration of a substance? Does this condition arise ...
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Unit cell of CdCl2

I understand that $\ce{CdCl2}$ has a rhombohedral unit cell as shown in this book. However I often find it being referred to as a "CCP analogue" of $\ce{CdI2}$. Presumably it is the chlorides which ...
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Is Polymorphism accompanied with an energy change?

Differential Scanning Colorimetry (DSC) is a technique used to identify Polymorphism by revealing two melting points of a pure crystalline structure. DSC shows a peak associated with the formation ...
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Allotropy and polymorphism

Polymorphism is defined as the ability of a solid material to exist in more than one form or crystal structure, whereas allotropy is defined as the property of some chemical elements to exist in two ...
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Amorphous to crystalline: Opposite trend?

Well my book says that on heating- amorphous solids crystalline at some temperature. As far as I know , amorphous solids have a very disordered structure compared to crystalline solids and on further ...
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How to measure band gap of powder sample with using diffuse reflectance method

We have UV SHİMADZU 2550 and its diffuse reflectance attachment. I want to measure band gap of single crystal samples. What should I do? Which formulas should I use to calculate band gap? I don't have ...
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Having trouble understanding the iron-carbon phase diagram

At room temperature, alpha and alpha+$\ce{Fe3C}$ are present (depending on carbon content), which is ferrite and pearlite. In the lab we polished and etched samples of carbon steel to observe the ...
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Correlation between crystal structure and underlying atomic properties

Can the crystal structure of an element/metal be explained by any underlying atomic or quantum mechanical properties of the element or is it an intrinsic property by itself (like atomic number)?
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Is there an experiment that visibly shows the effects of metastability?

I am attempting to create an experiment to show the effects of metastability to a public audience and get people excited about science. More specifically, I am wondering if there is any sort of liquid ...
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How to run crystal simulation on GAMESS?

I know GAMESS is not best suited for crystal simulation but I am not ready to start learning another package as VASP. As I heard GAMESS is able to do some calculations in a "terminated" crystal (I ...
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Replacement for optical calcite (Glan Thompson prism)?

I notice that Glan Thompson prisms seem to be the preferred optics for doing polarimetry and have been for at least 75 years. One instrument maker says that polaroid films can be used but they tend to ...
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Possible to grow optical calcite?

I notice that most optical calcite for sale seems to be from natural (mined) sources. Also, I know in World War 2, mining optical calcite was a strategic objective. Is there some reason why ...
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How do you calculate a unit cell's dimensions from an XRD spectra?

My Inorganic lab had us do an XRD measurement, but I've never been explained how to interpret the data. Question Calculate the unit cell dimensions a,b, and c, for $\ce{YBa2Cu3O7}$ from the ...
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Why does the sodium acetate solution crystallize by touching? [closed]

As the title stated above, why and how does the sodium acetate solution crystallize by touching?
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Why do people assume 28 oxygens in chlorite mineral formula?

I have been trying to calculate chlorite mineral formulas from microprobe data. However, all of the mineral formula spreadsheets on the internet, including those from the Open University assume 28 ...
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Crystal Lattice Defects

Why do defects in crystal lattices of various molecules and compound occur ? Is it due to the continuous contact or it arises due to impurities and human error during the formation?
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What does delta letter mean in some ceramics chemical material formula?

Here is a given chemical formula for ceramic material: La0.6Sr0.4Fe0.8Ni0.2O3-δ There is a letter δ. What does it stand for? I guess it is something about oxygen vacancies in crystal lattice.
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Interpreting X-ray diffraction data

So I've got my data for some x-ray crystals of small molecules of Ag, Cu,... I was curios to know what the best way to determine what type of lattice each of these atoms may have?
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Equivalent points for 3 fold and 6 fold symmetry

In a crystal Lattice how to find the equivalent points for 3 fold and 6 fold symmetry?
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Structure of Metallic Hydrogen

I am simply curious what the theoretical arrangement of metallic hydrogen would be. I found this article which gives a picture, but I don't understand what the labels mean (e.g. is H5 an isotope, ...
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Can alloys or ceramics have higher density than elemental solids?

Are there any examples of alloys or ceramics that have higher density than their densest elemental constituent? If so, do they have unusual or difficult synthesis processes? If not, is it provable ...
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Does mercury fulminate really look like crystal methamphetamine?

In the AMC series Breaking Bad , Walter (aka Heisenberg) smuggles in a bag of mercury fulminate under the guise of crystal methamphetamine and threatens to blow the room up if he doesn't get his ...
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Is there anything akin to molecular chirality for crystalline?

For example, in hexagonal closed-packed (HCP) structure, the atoms may be arranged in ABAB stacks or ACAC stacks. Can these two be considered enantiomers? Do they possess different solid state ...
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How is “F2/sig(F2)” the data quality in SXRD?

When I recieve a dataset from single crystal X-ray diffraction, I can determine the quality from a graph in which F2/sig(F2) is displayed in dependence of the frame. But I forgot the basics... I have ...
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Can a network covalent solid be amorphous?

All the definitions I'm seeing give examples of crystalline solids like diamond or boron nitride. But I'm wondering if it also includes amorphous macromolecules like vulcanized rubber. I'm thinking ...
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Rock Salt structure

Source BY looking at this structure of rock salt (NaCl) we can say that the chloride ions and the sodium ions have the same environment that is the nearby atoms position relative to that ion except ...
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Why is sand, sand; and why is glass, glass; While both mainly contain Silicon Dioxide?

I know that there is the famous process of heating material and converting them to glass; but what I don't know is, what is the chemical process of the creation of glass? Is it crystallization? How ...
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Etching around corners

In etching of mono silicon, why does the etching process around the corners differ from the etching process around the flat edges? What brings about this difference and is there some way that MEMS ...
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How do I make PDB 1HIG's data usable for producing ball-and-stick models?

PDB: 1HIG, when opened using Accelrys DS Visualizer, Avogadro and Jmol produces a series of dots in space and cannot be displayed as 3D ball and stick models. Is there any way to overcome this ...
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Is it possible to construct a 3D molecular model using x-ray powder diffraction data?

I've got x-ray powder diffraction (XRPD) data on bendamustine HCl from a patent and I want to know how to construct a 3D model using this data with software.