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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Isolating radium oxide
Why is radium oxide yet to be isolated when a wide range of other radium (II) compounds are known ?
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Why does the dielectric constant of a solid increase due to a Frenkel defect?
In crystalline solids, an atom may be displaced from its original position in order to create a vacancy in the original location. This is referred to as a Frenkel defect. Why does this defect result ...
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Correct Definition of Absolute Electrode Potential
I thought absolute electrode potential is Galvani potential difference at the interface. However, it is given by following equation in John Bockris - Modern Electrochemistry (Ref.1): $$ E^M \mathrm{(...
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Interstitial sites: edge and face sharing?
In close packed structures there is one octahedral hole per close packed atom. In a HCP unit cell these octahedra form a chain of face sharing polyhedra. Is this this universal in close packing or ...
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How is the Born-Lande equation modified when the structure is not NaCl?
Often the Born-Lande equation is quoted (alongwith the calculation of the Madelung constant and Born exponent) with reference to rock-salt structure. But what if we take some other crystal, like ...
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Effect of temperature and pressure on structure of solids
What is the effect of these conditions on the structure of solids? My book has the answer that confuses me. I got nothing about it. Can you please explain? The answer of the book is
With the ...
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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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Why is ruthenium dioxide a conductor while titanium dioxide is an insulator?
Ruthenium dioxide has the same crystal structure as rutile (titanium dioxide), and the metal atoms are in the same oxidation state. Yet ruthenium dioxide is a metal-like conductor (its resistivity is ...
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Brillouin zones of a compound after structural relaxation
My background in solid-state chemistry isn't much, so I apologize in advance if there arises the need to raise a basic fact while answering my question. I've been learning mostly from the web, with my ...
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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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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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Electrical and thermal conductivity of graphite
I was reading about carbon family where it was mentioned that electrical conductivity of graphite increases with temperature while thermal conductivity decreases.
However, I could not find a suitable ...
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Comparison between Boron Nitride and Graphite: Interlayer distance
Boron-nitrogen chemistry has attracted significant attention, partly because a B–N unit is isoelectronic with C–C. Furthermore, the radius of carbon and its electronegativity are roughly the
average ...
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Why are certain reflections forbidden in body centered cubic and face centered cubic structures?
I know that for body centered cubic structures the allowed reflections only happen if h+k+l is even and reflections are forbidden is h+k+l is odd, and for basic face centered cubic structures (...
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Is hydrolytic polymerisation the mechanism by which the precipitate forms from the neutral complex?
From basic coordination chemistry and acid-base equilibria we understand that a metal hexa-aqua ion can be deprotonated until it's positive charge is balanced by the negative charge of the hydroxides ...
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Cationic vacancies created when non-stoichiometric iron oxide is doped with silicon(IV) ions
Problem
It is believed that non-stoichiometric compound $\ce{F_{0.93}O}$ forms by doping of $\ce{Fe^3+}$ ions in $\ce{FeO}$ crystal by replacement of $\ce{Fe^2+}$. Calculate the number of cationic ...
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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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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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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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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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What makes up the conduction band?
Prologue/Rant about online classes
We have been taught the electron sea model to explain metallic bonding and conduction of electricity by metals. Then out of the blue, the band theory was introduced, ...
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Putting high symmetry points labels to a band structure plot
So far I've got this plot using Quantum Espresso. I want to put gamma, X, L, etc labels to the k-path.
Quantum Espresso's ouput states the following:
...
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Body centered cubic lattice vs Primitive cubic unit cell
I was reading about Bravias lattices(cubic crystal system) when got confused about an article in my book.
Please refer to Counting body center as lattice point when basis consists of 2 atoms.
The ...
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Single crystal LiF solid state NMR
I haven't been able to find any literature on $\ce{^{19}F}$ solid state NMR studies of $\ce{LiF}$ crystals, not even $\ce{LiF}$ powders. Is there any NMR chemists who is familiar with $\ce{LiF}?$ Any ...
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Defects in crystalline structure
Starting from a perfect $\ce{MgO}$ crystal a solid solution of $\ce{Al2O3}$ and $\ce{MgO}$ is prepared with an atomic proportion of $15:85$ of $\ce{Al}:\ce{Mg}$. Knowing the number of vacancies per $\...
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Compound metal oxide stoichiometries
When certain oxides are combined in a pre-determined stoichiometry and synthesized with a ceramic-like synthesis process(power-in-tube), multiple phases may be obtained which not necessarily is same ...
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388
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Solid State - Radius Ratio rules
Why lithium salts crystallize in octahedral lattice , although radius ratio values are much below than expected ratio?
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Voids vs Interstitial Site?
I am studying solids states.
So we studied different lattices of Ionic solids by introducting smaller Cations into VOIDS.
Next topic is of defects. SO it is written Frankel defect arises when a ...
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19F MAS NMR chemical shift tensor and the crystal structure
$\ce{^{19}F}$ MAS NMR is measured on fluorine-doped $\ce{TiO2}$. $\ce{F}$ is to substitute $\ce{O}$ and the crystal structure is anatase, which has a tetragonal crystal system with a space group $\ce{...
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Band alignment of heterojunctions
I have seen several band bending diagrams in journals and the web. However, I am not sure as to how they align them. Some diagram appear to align the vacuum level and some align them by Fermi Level. I ...
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Reference request for properties of amorphous titanium carbide (a-TiC)
I assume through some side reaction I'm getting $\ce{TiC}$ in my $\ce{TiO2}$ samples after calcination and I need some basic information about the properties of amorphous $\ce{TiC}$.
Is it ...
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Is there a compound where one element has a CCP structure with all voids occupied by others?
My Google-fu hasn't got me anywhere. All results have been quite fuzzy about it, nothing explicit.
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Why does aluminum chloride have a higher lattice energy than aluminum fluoride?
From the table below (source: McMurry's Chemistry [1, p. 212]), it is evident that $\ce{AlCl_3}$ has a higher lattice energy than $\ce{AlF3},$ even though $\ce{F}$ is smaller than $\ce{Cl}$. Why is ...
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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 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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High symmetry points and x-coordinates
Is it possible to work out the x-coordinates related to high symmetry points?
The software I'm using doesn't provide me with that, so I was wondering if there is a way to manually figure it out, as I ...
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Pressure vs electric conductivity in solids
If we apply pressure to a solid, does it change its electric conductivity? I am asking this because in 2020 they announced a superconductor at room temperature but under a pressure of 3/4 of the ...
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How to calculate planar density of a face /plane of crystal with cation and anions?
Planar density is given by numer of atoms in plane /plane area .
Suppose I want to calculate
planar density of 100, 101 and 111 planes of Nacl. Radius of Na+ and Cl- ions is 0.086 nm and 0.126 nm.Na+ ...
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0
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Unit cell in a hexagonal closed pack structure
My textbook says that there are only 14 possible 3D lattices(Bravais Lattices).
One of these 14 lattices is a hexagonal lattice in which only a primitive variation is given to be possible.
But then I ...
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Sphalerite type structure
There are binary diamond type structures for example S and Zn form sphalerite. I thought the reason this formed was because of the big difference in the radii of the atoms that allows the smaller atom ...
1
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0
answers
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Finding ionic radii from solubility data and density
$\pu{5.35 g}$ of a salt $\ce{ACl}$ is dissolved in $\pu{250 ml}$ of solution. The $\mathrm{pH}$ of the resultant solution was found to be $4.85.$ Find the ionic radius of $\ce{A+}$ and $\ce{Cl-}$ if ...
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How do hard drives store information using magnetic layering? (Antiferromagnetic/ferromagnetic films)
I am doing some work with solid state materials in some chemistry courses and I've been doing some research into exactly how a hard drive stores information as 1's and 0's. It seems like a bunch of ...
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Packing fractions of HCP and FCC
The packing fractions of hexagonal close packed unit cell and face centred cubic unit cell come out to be same when calculated geometrically.
Is it just a coincidence? Differently put, could it be ...
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charge transfer between layers of graphite with stacking fault
As a general rule, we only expect two parts of a system to have the exact same amount of charge if they are symmetry-related to each other. How much charge transfer would occur in graphite with a ...
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Diffusion equation I can't seem to find anywhere
So I was looking through some old lecture notes from a few years back when I stumbled upon a useful and simple equation that should, according to my former professor describe the diffusion in solid ...
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What does this chemical formula mean?
Wikipedia says the formula of aluminum oxynitride is this $\ce{(AlN)_x·(Al2O3)_{1−x}}$,
$0.30 \leq x \leq 0.37$ . What does this formula mean?
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What are the effects of frenkel and schottky defects on electrical conductivity of a solid?
How do these two defects impact dielectric constant of solid? Please explain these two questions in detail.
In case of frenkel defect the the smaller ions are just dislocated from their initial ...
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Is Body Centred Cubic arrangement also a kind of packing in solids?
I am confused about the packing thing in solids . I read about Hexagonal Closed packing(HCP) and Cubic closed packing(CCP) then realised this stuff named as Body Centred Cubic(BCC) under the heading ...
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NiO and ZnO electrical conductivity with oxygen pressure
NiO is a Mott-Hubbard insulator and increasing oxygen concentration leads to anion excess and oxidation of Nickel so electron hopping is more favourable so electron repulsion is reduced and it becomes ...
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Substituting Ulexite
I'm working on ceramic glaze chemistry. One ingredient I don't have, but want to substitute is ulexite:
$$\ce{NaCaB5O6(OH)6.5H2O}$$
I have borax, calcium borate, and calcium silicate:
$$\ce{NaB4O7 ...
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