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.
76
questions with no upvoted or accepted answers
7
votes
0
answers
324
views
Isolating radium oxide
Why is radium oxide yet to be isolated when a wide range of other radium (II) compounds are known ?
- 2,500
6
votes
0
answers
103
views
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{(...
- 823
6
votes
0
answers
182
views
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 ...
- 953
6
votes
1
answer
2k
views
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 ...
- 61
5
votes
0
answers
151
views
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 ...
- 385
5
votes
0
answers
4k
views
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 ...
- 161
4
votes
0
answers
129
views
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 ...
- 213
4
votes
0
answers
124
views
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 ...
- 106
3
votes
0
answers
141
views
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{...
- 31
3
votes
0
answers
370
views
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 ...
- 113
3
votes
0
answers
2k
views
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 ...
- 3,632
3
votes
0
answers
1k
views
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 (...
- 389
3
votes
0
answers
46
views
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 ...
- 953
3
votes
1
answer
179
views
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 ...
- 401
2
votes
0
answers
31
views
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 ...
- 4,182
2
votes
0
answers
48
views
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 ...
- 121
2
votes
0
answers
36
views
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 ...
- 21
2
votes
0
answers
89
views
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, ...
2
votes
0
answers
773
views
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:
...
- 121
2
votes
0
answers
1k
views
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 ...
- 191
2
votes
0
answers
85
views
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 ...
- 121
2
votes
0
answers
44
views
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 $\...
- 257
2
votes
0
answers
56
views
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 ...
- 41
2
votes
0
answers
360
views
Solid State - Radius Ratio rules
Why lithium salts crystallize in octahedral lattice , although radius ratio values are much below than expected ratio?
- 113
2
votes
0
answers
2k
views
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 ...
- 391
2
votes
0
answers
86
views
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{...
- 517
2
votes
0
answers
63
views
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 ...
- 4,236
2
votes
0
answers
44
views
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 ...
- 517
2
votes
0
answers
75
views
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.
- 1,266
2
votes
1
answer
3k
views
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 ...
- 2,019
1
vote
0
answers
62
views
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 =...
- 121
1
vote
0
answers
55
views
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 $...
- 39
1
vote
0
answers
68
views
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 ...
- 11
1
vote
0
answers
89
views
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 ...
- 135
1
vote
0
answers
59
views
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+ ...
- 11
1
vote
0
answers
24
views
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 ...
- 45
1
vote
0
answers
38
views
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
vote
0
answers
188
views
Why is liquid germanium denser than solid germanium?
Why are some elements like Ge and Si have liquids denser than their solids? In water it is explainable by H bonding, but no H bonds or such are there in Ge and Si.
Well, I want an explanation about ...
1
vote
0
answers
105
views
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 ...
1
vote
0
answers
124
views
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 ...
1
vote
0
answers
604
views
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 ...
- 409
1
vote
0
answers
25
views
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 ...
- 597
1
vote
0
answers
37
views
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 ...
- 4,182
1
vote
0
answers
52
views
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?
- 239
1
vote
0
answers
716
views
To what extent are the radius ratio rules valid for predicting the crystal structure of an ionic compound?
The ionic radii of $\ce{Ba^2+}$ and $\ce{O^2-}$ in barium oxide are $\pu{135pm}$ and $\pu{140pm}$, respectively. The ratio of the radius of $\ce{Ba^2+}$ to $\ce{O^2-}$ is approximately $0.964$.
...
- 825
1
vote
0
answers
1k
views
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 ...
- 41
1
vote
0
answers
76
views
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 ...
- 19
1
vote
0
answers
158
views
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 ...
- 9,636
1
vote
0
answers
410
views
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 ...
- 1,147
1
vote
0
answers
23
views
Surface-dependency of kinetic in speed law?
we can comprehend the quantitative dependency of the kinetic of a chemical reaction through the speed law: $v(t) = k \cdot c(...)^k \cdot c(...)^n$
Here I used the concentration $c$ for that take ...
- 401