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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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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Density of Interstitial compounds
I have read in my textbook (not very reliable) that density of interstitial compounds is lesser than parent compound. But how can this be true?
We add atoms to the lattice voids, so density should ...
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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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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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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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On the exact definitions of Frenkel and Schottky defects
The wiki page on vacancy defects says;
It is also known as a Schottky defect, although in ionic crystals the concepts are not identical.
As far as I'm aware, they're the same. Furthermore, the wiki ...
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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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Lattice enthalpy and ionic character
As we move down in sulphates of group 2 their solubility decreases because there is a drastic decrease in hydration enthalpy as compared to decrease in lattice enthalpy.
Does the decrease in lattice ...
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Why is cuprous oxide a p-type semiconductor?
Wikipedia — Copper(I) oxide says $\ce{Cu2O}$ has semiconducting properties without any explanation.
Nolan [1] talks about $\ce{Cu^+}$ vacancies making copper(I) oxide an extrinsic p-type semiconductor,...
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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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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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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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Number of octahedral and tetrahedral voids present in a HCP structure
The given image depicts the tetrahedral and octahedral voids in HCP structure.
For the tetrahedral part
I figured out that there would be 6 tetrahedral voids in total.
My visualisation: In the ...
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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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How does lime prevent soda lime glass from dissolving in water?
How does lime addition as an ingredient prevent soda lime glass from dissolving in water? Does it form calcium silicate in the process of melting?
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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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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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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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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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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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Understanding Equivalent Wyckoff positions
I'm somewhat confused by the concept of Wyckoff positions in crystal structures. From Quantum Chemistry of Solids by Robert Evarestov, the definition of a Wyckoff position is "all the crystallographic ...
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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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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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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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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 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 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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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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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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Unexpectedly low melting point of Aluminium
According to Wikipedia, the melting point of aluminium is 933.47K (660 ºC) while the melting point of magnesium is 923K (650 ºC), yet the melting point of sodium is merely 370.87K (98 ºC).
Huge ...
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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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Is there an element with no liquid state? [closed]
I know this question might be dumb but, is there an element that will go directly from solid to gas, with almost no visible or no liquid state? Just a random curious question.
I am asking if there is ...
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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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How can a vacancy defect be a stoichiometry defect?
NCERT (India) explain stoichiometric defects as those defects which do not disturb the stoichiometry of the solid. Vacancy defects are stated to be under the category of stoichiometric defects. When ...
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Clarification of term symbol explanation of laser crystal doping from textbook
I am currently studying the textbook Diode Lasers and Photonic Integrated Circuits, second edition, by Coldren, Corzine, and Mashanovitch. Chapter 1.2 ENERGY LEVELS AND BANDS IN SOLIDS says the ...
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