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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Chemistry of Rutile, CdCl2 and CdI2
During lectures, we were told that 3d transition metal fluorides generally prefer a rutile structure. Chlorides prefer a $\ce{CdCl2}$ structure where $\ce{Cl-}$ adopt a CCP lattice and the metal ...
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"Fireblob" in KO₂ and PCl₅ reaction
The reaction between $\ce{KO2(s)}$ and $\ce{PCl5(s)}$ leads to the strange formation of a black "fireblob" which eventually turns orange.
This is demonstrated in this YouTube video (...
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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 does the 2+ oxidation state of Gold typically not occurr? [duplicate]
I'm currently researching a material containing gold in various oxidation states as part of my graduate school project. In the literature I found compounds where gold occurs in a 1+ and 3+ oxidation ...
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Band structure of solids in general
As my last question (Semiconductors and their electronic bands) was badly structured, I decided to elaborate my questions a bit.
As I now know, every solid/liquid forms a band structure, so all ...
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Can any compound form into an amorphous solid?
I am curious whether it is possible or not to make any solution of a specific compound into a crystal lattice or into an amorphous solid? I know that crystals form under specific conditions but seem ...
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Are there tenebrescent minerals like KCl, but ideally resettable with UV/IR?
Is there a ‘simple’ mineral that is tenebrescent (getting reversibly darker on irradiation), but is resettable with UV or IR?
Hackmanite, spodumene and tugtupite (Wikipedia examples for tenebrescence) ...
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Number of particles at a distance of √11 (a/2) from a single particle in a body centered cubic lattice
Take a particle on BCC lattice and from that we have to find number of particles at a distance of $\displaystyle \sqrt{11} \cdot \frac{a}{2}$ (where a is side length of cube). For this, the answer ...
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Why is there a point of orbits along with quantization in case of energy gaps?
As per my textbook and online sources. The definition of Energy bands I have found is this:
A) Energy levels:
( In a simplified view of an electronic structure of a single atom or isolated molecule.
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Why is silver(I) phosphate so unexpectedly thermally stable?
Silver(I) oxide is completely decomposed in air already at $\pu{300 °C}.$
Formulate the decomposition reaction and the corresponding mass action expression.
$\ce{Ag3PO4}$ can be melted at $\pu{800°C}$ ...
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Do molecular orbitals in metals form bands like in wave interference? [closed]
For bond that's formed between two identical atoms, I naively understand that one molecular orbital is a bonding orbital and the other is an antibonding one, and I believe they have to do with the ...
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Why does KCl have FCC structure instead of BCC?
I have this table here.
\begin{array} {|r|r|}\hline \text{Radius Ratio} & \text{Coordination number} & \text{Type of Void} \\ \hline <0.155 & 2 & \text{Linear} \\ \hline 0.155-0....
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How to express the lattice parameter of NaCl in terms of ionic radii? [closed]
In the $\ce{NaCl}$ lattice, $\ce{Cl^-}$ takes the FCC configuration, and all the voids at the edge and body center are filled by $\ce{Na^+}.$ So, do we calculate the edge length of unit cell $a$ as
$$...
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Does thorium(IV) oxide has a "fluorite" like structure? [closed]
The fluorite structure shows 8:4 coordination. Which of the following solutions has fluorite-like lattices?
$\ce{CaF2}$
$\ce{SrCl2}$
$\ce{BaF2}$
$\ce{ThO2}$?
My book tells me only $\ce{CaF2}$, $\ce{...
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Drying Li2CO3 without vaccum
I am looking for drying Li2CO3 without a vacuum oven, simply because we do not have one.
I did not find anything in the literature, or I am overthinking it? Just 100 °C overnight in a normal oven, and ...
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Are the density of states of bonding and the corresponding antibonding states complementary?
As for the bonding and the corresponding antibonding molecular orbitals formed between two types of atomic orbitals, are their density of states (DOS) complementary? This means if the DOS of the ...
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The existence of anti-phase boundaries (APBs) in defective crystalline materials
The existence of anti-phase domain boundaries (APBs) in polycrystalline materials is usually established by electron microscopic techniques (SEM/TEM) [1] and is also discussed in diffraction data ...
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Why are certain lattices compatible with only certain point groups and not all point groups?
I will limit this discussion to 2 dimensions for ease of intuition. My understanding of the 17 crystallographic plane groups is that these 17 groups represent all the possible symmetry groups of any ...
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Crystal structures exhibiting dimeric arrangement of tetrahedrally coordinated cations
I am looking for inorganic crystal structures that exhibit tetrahedrally coordinated cations arranged in a vertex-sharing dimer arrangement, where the cation - shared vertex - cation angle is close to ...
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What is the inconsistency in calculating the differences in Na2O and NaOH in solids (v2)?
(Note that this question has been fully edited for clarity, SE help advised not to delete the question and post another).
Background:
I have a computer model in which I feed it input data from various ...
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Regarding colour visibility due to F-centre
Below shown image is a cut out from the NCERT book.
Referring to the highlighted sentences:
I know that an $\ce{e^-}$ absorbs and emits light of a particular wavelength when bound in an atom and ...
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Factor Group Analysis of Na2SO4 - Site Group Symmetry
I'm still trying to understand how to construct a factor group analysis for a given molecular point group and the resulting solid state group symmetry. For this I searched for some examples and found ...
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How do different x-ray tube emission profiles (i.e copper vs cobalt sources) affect XRD samples containing iron (results included)?
Background:
I'm a student and have recently done some XRD on some iron ore mine tailings which came from an Australian mine tailings storage dam. The redness in colour and industry source led me to ...
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Why and how are mullites (and in extension solid solutions) formed and how are their formulas conceived as opposed to regular crystalline solids?
From doing more Phase ID for XRD on aluminosilicate based coal fly ash samples, I've seen mullite phases appear a few times which have the non-stoichiometric chemical formula $Al_{4+2_x}Si_{2-2x}O_{10-...
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Is there any calcium carbonate analogue drawing carbon from dry air?
Is there a nonliving (wood does not count) substance or process that accretes a solid material by withdrawing carbon from the air, in a manner analogous to calcium carbonate being accreted from ...
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Solid state chemistry current in tunnel diode [closed]
I am interested in this subject: Applied Mathematics in Electrical Engineering. I am interested in finding an expression for the tunnel current of a tunnel diode in the negative differential ...
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Why can we use the arrhenius equation to measure the number of vacancies in a material?
In a materials science video I was watching today the prof. said we could use the arrhenius equation to estimate the number of vacancy point defects in a material. And gave the following equation:
Nv =...
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What are some good synthetic samples I can make myself to start getting better at Quantitative X-Ray Diffraction?
I'm a student wanting to become an expert in quantitative X-Ray Diffraction (QXRD) to determine the wt%s of both crystalline and amorphous phases in a solid specimen. At my university I have access to ...
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How does heating alkali metals with graphite change its conductivity and density?
My textbook says when heating potassium, rubidium, cesium with graphite, the metals react by invading the space between the layers. They form highly colored interstitial carbides that are non ...
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Is there a chemical compound which does not have a liquid state but a solid and a gaseous state? [duplicate]
Is there a chemical compound which does not have a liquid state but a solid and a gaseous state? Meaning no matter the temperature or pressure it will never be in its liquid form. According to my ...
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Why is diamond not the most dense substance?
Diamond is the hardest substance on earth which can be attributed to its tightly-bonded crystal lattice. Hence, assuming there were a substance more dense than diamond (which there are), mustn't it be ...
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How do you write fractional hydrates in words?
Apart from sequihydrate and hemihydrate (1.5 and 0.5 respectively), I can't find a way to write any other fractional hydrates.
Wikipedia states:
The notation "hydrated compound⋅nH2O", where ...
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What is m.2m point group?
I'm using Bilbao Crystallographic Server to find 3D crystallographic point groups of the K points of anatase TiO2.
Since the space group of anatse TiO2 is $I4_1/amd$, on this page, I found the point ...
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How Amorphous solids are converted to Crystalline?
I know about a process of Annealing where a crystalline solid is heated to its melting point and then cooled rapidly so as to form amorphous solid which has random crystallite in uts structure.
But ...
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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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How do other elements fit into a diamond's carbon lattice (e.g. nitrogen in yellow diamonds)
Traditional pure-carbon diamonds have a simple structure (tetrahedral, if I'm not mistaken). But common types of diamonds have other elements within them. For example, yellow diamond has nitrogen in ...
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What is the net gain of charge carriers in a semiconductor if an atom is removed?
In pure germanium, all Ge atoms are bonded with a tetrahedral geometry. It has a band gap and is a semiconductor. If we remove one Ge atom, what type(s) and how many charge carriers will be generated? ...
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why an interstitial defect increases density in covalent solids and do not increases in ionic solid?
The interstitial point defect increases the density of a solid. Frenkel defect is also a type of this defect but it do not increases the density.
Also, the mass / volume concept of density tells us ...
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Two atoms exist in the same coordinate position in the lattice?
I am trying to simulate the properties of FeF3(H2O)3, so I download its crystal structure file from Crystallography Open Database, but it seems that in the lattice, ...
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In calculating the radius ratio in a tetrahedral site in an FCC lattice, why do we take tetrahedral void in the middle of the body diagonal line? [closed]
When calculating the ratio of cation / the ratio of anion in a Tetrahedral system in an FCC lattice, why do we take the void to be in the center instead of it being √3a/4 from the corner.
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Why does density decrease when pressure is increased on an NaCl type lattice?
I was told that the effect of pressure on an NaCl type structure would make the atoms come closer and therefore change the type to CsCl type making Z (no of atoms per unit cell) go down, hence density ...
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What is the paramagnetic susceptibility of sodium at around room temperature?
Proposed solution:
This question comes from Tanner's manual Introduction to the Physics of Electrons in Solids, at the chapter dedicated to the application of the Fermi gas model. The Fermi energy is $...
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Restoring potential of atoms in a solid
Above $\pu{0 K}$ the atoms in a solid are vibrating. However, what kind of potential restores each atom in the starting position?
Consider the crystal lattice of NaCl. The potential energy of a $\ce{...
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Balancing a chemical reaction with oxidation numbers
We have been teached how to balance chemical reactions with oxidation numbers in school, but somehow I can't understand it.
This is the equation to balance
$$\ce{Cu(s) + NO3−(aq) + H+(aq) -> Cu^2+(...
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Why Lambert's law does not hold for photoresistors?
Why don't photoresistors made of Si obey Lambert's cosine law? Is it related to the dark current of the photoresistor? I couldn't find any solution while searching the web.
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Comprehensive list of metal alloys along with Moh's hardness scale
Material property lists, such as springermaterials.com, has lists of metal alloys and their properties. Is there a similar website that lists alloys along with their Mohs scale hardness? For ...
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Why can't the Fajans' rule and lattice energy theory be used to explain the difference in thermal stability of magnesium and calcium carbonates?
$\ce{CaCO3}$ is more thermally stable than $\ce{MgCO3}.$ I do understand that a larger cation would be able to stabilize a larger anion to a greater extent, but why can't we use Fajans' rule or ...
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Why do silver halide crystals in suspension, develop a surface charge
This is a question related to analog photography. Photographic films have a suspension of silver halide crystals in them, and these crystals have adsorptive properties which are used in this ...
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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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Is dehydration of cobalt(II) chloride hexahydrate dynamic equilibrium?
I know that the dehydration of cobalt(II) chloride hexahydrate is a reversible reaction, is it a dynamic equilibrium?
$$
\begin{align}
\ce{CoCl2·6H2O &<=> CoCl2·2H2O + 4 H2O}\tag{R1}\\
\ce{...
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