Questions tagged [crystal-structure]
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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Was there an issue with polymorphs in growing synthetic quartz crystals?
Today, I read an article, The Rise of The Disappearing Polymorphs, about unwanted polymorphs ruining production of various organic chemicals, such as pharmaceuticals paroxetine hydrochloride and ...
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Why ABO3-type oxide perovskites are so stable?
"ABO3-type oxide perovskites are characterized by high structural stability, which makes it possible to dope them in a relatively wide range of dopant concentrations." What really causes ...
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Why MgB2 is superconductor and AlB2 not?
MgB2 and AlB2 crystallize in a hexagonal system in the structure shown below. The lattice constants c are 0.352 and 0.325 nm, respectively. MgB2 is a superconductor and AlB2 is a semiconductor. What ...
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Why ionic compounds don't usually crystalize in zinc blende structure?
Why ionic compounds (I mean the character of bonding) don't usually crystallize in zinc blende structure, but covalent ones do, even if it is not expected from the radius of atoms?
For instance AgI ...
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Brilliant fluorescent properties of Na2S(x) obtained from Na2SO3 or Na2S2O3
When $\ce{K2SO3}$ or $\ce{Na2SO3}$ is heated strongly by any method (in a flame, in an electric arc, on a metal plate in an induction heater), the resulting residue should be a mixture of $\ce{Na2SO4/...
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Is the acceleration of the low-temperature allotropic conversion of β-form white tin by the presence of α-form grey tin really considered catalysis?
discussion of the allotropes of sulfur in Melting point of sulfur and comments below reminded me of Napoleon's buttons, cf. Tin pest; Allotropic transformation. That section in its entirety reads:
At ...
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Undiscovered kinetically-hindered metastable phases
The majority of solid chemicals have multiple meta-stable phases. This means that there are multiple different crystal structures that are kinetically stable. For example, aragonite and calcite are ...
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Would fluorides stabilize zirconia?
The reason for zirconia's cubic and tetragonal phases not being stable is that the cation-anion ratio is too small for proper contact between ions.
One way is to use other oxides that have a bigger ...
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Small-Angle X-Ray Scattering of Bulk Polymers
Does anyone have any recommendations on how to get useful information from SAXS of polymers when the system is not dilute?
This is the type of data we're working with:
My understanding is that since ...
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Crystal lattice structure from single crystal x-ray diffraction pattern
Is there a good reference describing the inverse problem of determining the crystal lattice, unit cell etc., from a single crystal x-ray diffraction pattern and chemical composition? I am looking for ...
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Constituents of LaI2 [closed]
An ionic solid $\ce{LaI2}$ shows electrical conduction due to presence of which anions and cations?
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growing flawless NaCl crystals
Simple experiments on the internet show how to grow salt (NaCl) crystals, but the crystals are small and flawed. Several companies sell flawless optics, like windows, made of NaCl, which are ...
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Does CsBr have BCC lattice or cubic?
Everywhere I see on the internet, it says BCC, but my professor still says "it is cubic lattice, no matter which book/website might tell you otherwise".
The argument was that for deciding ...
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Why Green Solution After Putting Bismuth Antimony in Nitrogen Acid
I am in a physics lab studying dislocation, and we submerged a bismuth antimony sample in nitrogen acid (about 50% concentration, if I remembered it right) as the first step to etch it. There were ...
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Why don't Zn, Cd, Mn and Hg have more than one metallic structure at normal temperature, while other d-block elements do?
It's been given in my book, that "With the exceptions of Zn,
Cd, Hg and Mn, they have one or more typical metallic structures at
normal temperatures."
But, why this exception?
