Questions tagged [solid-state-chemistry]
Study of chemical species that are in solid phase, either in cases of their properties, or about ways of synthesizing them.
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Why are there only 7 types of unit cells and 14 types of Bravais lattices?
Why are there only 7 types of unit cells and 14 types of Bravais lattices?
I was reading about solid-state chemistry for the first time and this limitation made no sense to me.
I tried to do the ...
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What makes Gorilla Glass more durable with each generation?
Gorilla Glass (GG) is one of the most recognizable brands of toughened glasses today, thanks to their marketing and widespread usage in various gadgets and automobile industry.
According to Wikipedia,...
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Why are there no cheap diamond equivalents?
We recently learned in school that diamonds sparkle as the are very optically dense, meaning that it takes longer for light to pass through them, thus meaning that the light totally internally ...
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How does NaCl maintain its crystalline structure?
My understanding is that $\mathrm{NaCl}$ is an ionic compound, in which $\mathrm{Cl}$ becomes (effectively) $\mathrm{Cl^-}$ and $\mathrm{Na}$ becomes $\mathrm{Na^+}$. So I understand why I would get a ...
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How are the number of tetrahedral voids twice the number of octahedral voids in a CCP structure?
How are the number of tetrahedral voids twice the number of octahedral voids in a CCP structure? Is there some kind of mathematical proof for it? Is there some way I can understand this intuitively?
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Are there any ionic amorphous solids?
This question on NaCl crystalization actually got me wondering: are there any ionic amorphous solids? Like ionic crystals are crystalline materials of electrostatically-attracted ions, can ions form ...
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How to solidify sand
I'm doing a research project where we analyzing the structure of sand after a certain process. To get a better idea of the internal structure of the sand, we use different colors to visualize the ...
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Contribution of Tetrahedral and Octahedral voids in HCP
I cannot find anywhere what the contribution of atoms situated at octahedral or tetrahedral voids in a HCP unit cell would be. I need to know this to be able to calculate the formula of a compound ...
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Why doesn't tantalum and tungsten form amalgam?
User @Poutnik has recently answered a question in which he quoted this statement from Wikipedia:
Almost all metals can form amalgams with mercury, the notable
exceptions being iron, platinum, ...
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Are chiral quasicrystals possible?
Quasicrystals are materials that have long-range atomic order but lack the translational symmetry of conventional crystals. All quasicrystalline tilings and packings I have read about thus far, whilst ...
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Stoichiometric defects in silver bromide
Stoichiometric defects (Schottky and Frenkel defects) in ionic crystals are formed due to irregularities in the ionic arrangement which maintain the stoichiometry and electroneutrality of the solid. ...
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How to calculate the height of an hcp lattice?
A hexagonal closed packing (hcp) unit cell has an ABAB type of packing. For calculating the packing fraction we require the volume of the unit cell.
Volume of hcp lattice = (Base area) $\cdot$ (...
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How does chromium help stainless steel prevent rusting?
Various sources (such as this one) say that stainless steel is stainless because a passivation layer of an oxide is formed, but I haven't found details on why chromium helps create this passivation ...
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Will a solid object lose or gain atoms on standing over time (without being acted upon by external influences)?
Suppose I'm in my room with my keyboard, my desktop and my desk. Are these objects losing or gaining atoms every second? Or are they forever stuck with the same number of particles until you scratch, ...
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Is there a theory behind selecting elements that may be successful in potential superconductors?
Looking at something like $\ce{YBa2Cu3O7}$ which was one of the first cuprate superconductors to be discovered, I'm always curious how the selection of these substances as likely superconductors comes ...
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Why is solid phase peptide synthesis limited to 70 amino acids?
I'm reading document about Solid phase protein synthesis (SPPS) from Wikipedia, and according to the document:
SPPS is limited by yields, and typically peptides and proteins in the
range of 70 ...
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What does β stand for in β-potassium zirconate?
What do the Greek letters (α, β, γ...) convey when they are prefixed to a crystalline substance?
For example: β-potassium zirconate
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How does the crystal know where to stop stacking the unit cells?
I tried to make different crystals in the cubic system by stacking cubes in a 3D software. However, I need to tell the software where to skip rows or stop stacking the unit cells in a specific ...
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What is "chemical pressure"?
While reading some publications on solid superconductors, I encountered a term "chemical pressure" a few times, which is usually attributed to the changes of superconducting transition ...
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Why does an ideal capacitor give rise to a rectangular cyclic voltammogram (CV)?
This question is sort of a sequel to my previous question about cyclic voltammetry (CV). One of the responses made reference to the fact that an ideal capacitor gives rise to a rectangular cyclic ...
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Physical meaning of thermal parameters dimension (Ų)
In single-crystal x-ray crystallography both isotropic and anisotropic displacement parameters $U_{ij}$ of thermal ellipsoids have dimension of square angstrom ($Å^2$) as follows from the definition ...
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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 ...
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How can brass still be made even though the crystal structures of zinc and copper are not the same?
Based on the Hume-Rothery rules, to dissolve an element into a metal, the crystal structures for both must be the same. But the structure for zinc is HCP, whereas copper has FCC structure. It does not ...
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Software for generating a lattice from a unit cell for molecular crystals?
I am looking for a software package which can take a unit cell (and lattice parameters, etc.) and from that generate a crystal lattice. Ideally it will have functionality for orthorhombic, hexagonal, ...
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Why are X-rays used in crystallography?
Can any other wavelength of electromagnetic radiation be used?
Why can't gamma radiation be used?
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What causes photovoltaic (solar) cells to degrade?
Photovoltaic panels can have 20 or 25 year underwritten warranties with a guaranteed remaining efficiency of 80 % of the new panel. That means, that photovoltaic panels seem to degrade somehow.
Why ...
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What is the reason for isotropy in amorphous solids?
In my book, it's been mentioned that crystalline solids are anisotropic whereas amorphous solids are isotropic in nature. The reason for these has been explained (with a diagram) as:
Crystalline ...
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Materials with solid volume greater than liquid volume
Water has a solid volume greater than its liquid volume.
This question is in two parts.
1) Are there other materials that have solid volumes greater than liquid volumes? 2) What about the structure ...
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What is the actual reason behind PCl₅ existing as an ionic solid?
Why does $\ce{PCl_5}$ exists in the solid state as $\ce{[PCl_6]^{-}[PCl_4]^{+}}$? What is the problem with it that it doesn't exist in its original form in solid state? Like why isn't it just $\ce{...
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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 ...
user1811
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Is there a way to turn alcohol into a solid gel?
I'm wondering if there is a way to turn alcohol or another bacteria killing substance into a solid gel form, sort of like the gel you can use to clean a keyboard.
Source: Aliexpress.com Computer ...
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Thermochromism in PbI2
I noticed while heating some PbI2 powder that it reversibly changes from a yellow to a dark red. However, I was unable to find anything on this thermochromism.
There are related cases in TlI and AgI ...
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Calculate the third and fourth nearest neighbours in bcc
My textbook has given data for third and fourth nearest neighbours to be 12 and 8 with distances $\sqrt{2}a$ and $\frac{\sqrt{11}a}{2}$.
I have been able to calculate for the first and second ...
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Are all lattices Bravais lattices?
Can all lattices be described as one of the fourteen Bravais lattices?
Is the hexagonal close packed structure also one of the fourteen Bravais lattices?
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Has QTPIE ever been applied to 1D metals such as polyacetylene?
QTPIE is a fluctuating charge model that substantially improves modeling of polarization and charge transfer. I was curious whether it has ever been applied to 1D metals such as polyacetylene to ...
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What is the oxidation mechanism of gunpowder?
I've been recently looking into fireworks and the chemistry of explosives, and I found out that, amongst others, one of the most important reactions in gunpowder ignition is the oxidation of charcoal ...
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Why are p-type solar cells more prone to degradation in space than the n-type ones?
Why are p-type (boron doped substrate) solar cells more prone to degradation in space than n-type (phosphorus doped substrate)?
All the sources I've looked at simply state it was found that p-type ...
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Distance between successive tetrahedral voids in FCC
What is the distance between successive tetrahedral voids in a FCC
crystal structure?
The distance between a face centered atom and a tetrahedral void is $\sqrt{\frac{3a}{4}}$ if the cube's edge ...
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What is the world's finest powder substance?
What is the world's finest powder substance that has the smallest granules but remains solid?
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How to predict the type of intrinsic defect? [closed]
Intrinsic defects occur when a pure material crystal shows either vacancy or interstitialcy. When an ionic compound has vacancy, the imbalance in charge has to be compensated with another defect. When ...
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Why are there exactly 5 types of two-dimensional lattices, and what distinguishes them?
In the book Chemistry: The Central Science, they introduced the following 5 types of two-dimensional lattices:
The book said that the blue square represents the unit cell, the black dots are lattice ...
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Calculating the strength of an ionic bond that contains poly-atomic ions
So the bond association enthalpy for ionic compounds like $\ce{NaCl}$ and $\ce{NaBr}$ can be easily calculated from a Born-Haber cycle. But the way a Born-Haber cycle is constructed it uses info that ...
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How can diamond have a fixed refractive index?
I was doing a lesson on solid states. There were given two kinds of solids namely amorphous solids and crystalline solids. Some differences between these two solids were given in my book. One of the ...
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Colour due to F-centre is same as that produced in a flame test, why?
I have noticed that the colours that the F-centres impart in Alkali metal halides are the same that the corresponding alkali metals impart to their flames.
$\ce{NaCl}$ when heated in an atmosphere of ...
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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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For a given packing (hcp, fcc, bcc), which ions occupy the corners and which occupy the faces or centers?
I recently came across the packing of atoms in unit cells. I wanted to know if there was a way to tell where the atoms in the unit cell are just by knowing the compound and its packing (hcp, fcc, etc.)...
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Why do we need to add hydrogen to amorphous silicon?
I was recently studying about Staebler-Wronski effect observed in amorphous silicon (a-Si). I realised it was due to imperfections in the lattice structure and breaking of Si-Si bond to Si-H bonds.
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Why is ZnFe2O4 a normal spinel?
Considering that $\ce{Zn^2+}$ is $\mathrm{d}^{10}$, $\ce{Fe^3+}$ is $\mathrm{d^5}$, and $\ce{O^2-}$ is a weak field ligand, the CFSE values of both the normal and inverse spinel structures should be $...
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How can the bulky octadecyltriethoxysilane molecule promote single-crystal growth?
Octadecyltriethoxysilane is very bulky (source),
yet it was used to promote single crystal growth (source). How can such a bulky molecule induce crystal growth? (For example epitaxial growth happens ...
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How to predict the 31P NMR spectra?
What can I predict about the $\ce{^{31}P}$ spectra of $\ce{TiP2O7}$?
To get the required information about the crystal structure of the compound
Here is a screenshot from the ICSD website:
Since ...
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