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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Is there an equivalent unit cell that can describe a bcc unit cell where all points are the same element?
Similar to how an NaCl-structure can be described as just a primitive cubic structure if all the lattice points were the same element or ion. I'm asking if there any such alternative for the CsCl-...
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Will ice be cold or not when formed using pressure? [closed]
We know that ice can be formed either by lowering the temperature of water or by applying more pressure. If we lower the temperature of water the ice so formed will be cool which is obvious.
If ice ...
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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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Counting body centre as lattice point when the basis consists of 2 atoms
An article in my book gives the following informatiom :-
I understood part a) and b) but faced problems with c).
It says that here the basis consists of 2 atoms which doesnt seem to be very ...
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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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How do phase transitions occur in the solid phase? [closed]
For example, how does graphite transform into diamond as pressure increases at a certain (adequate) temperature? I'm not sure if this is a great example to look at the bigger picture, so another ...
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Polyhedron with four capping ions
Let's say I have a trigonal prism in my crystal structure and this is further capped by two ions it's called a bicapped trigonal prism. If I have three ions it's called a tricapped trigonal prism. But ...
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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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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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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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How to determine the edge length of the aluminium unit cell?
I'm having trouble understanding why I can't get the correct answer from this homework problem:
Solid aluminum forms a face-centered cubic unit cell. Aluminum has a density of $\pu{2.70 g/cm^3}$. ...
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Does titanium(II) oxide conduct electricity? [duplicate]
In my book, it is given that $\ce{TiO(s)}$ is an electrical conductor. But I'd think that since $\ce{TiO(s)}$ is ionic and in solid state, it shouldn't conduct electricity. So, why does it conduct ...
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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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Synthesis of compound metal oxides [closed]
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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Concentration of electrons in silicon sample with a phosphorus dopant
I'm studying electrical and computer engineering and all I remember from chemistry is from high school. We have a $\ce{Si}$ sample and we want to replace one in every million atoms with a phosphorus ...
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Let us say that height of HCP is h then what is the distance of tetrahedral voids [closed]
In a hexaoal cose-packedstructue et $h$ be the spacing between equivalent basal planes. Then what are the "heights" of the tetrahedral voids lying between any two adjacent, equivalent basal planes, ...
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why lattice energy have to be greater than IE and EA? [closed]
Why is lowering effect of the lattice energy not able to be greater than the combined net energy raising effects of the IE &EA?
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Calculating nearest neighbor distances
For cubic materials, there are equations in which to calculate nearest neighbor (NN), second nearest neighbor, etc. Can this be done with tetragonal crystal structures? I want to calculate NN, 2NN, ...
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Which is the suitable process for ball milling?
Why do we mainly choose the wet ball milling process in spite of dry ball milling process? Both processes are used to make a homogeneous mixture of different compounds.
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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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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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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 $0.964$.
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Why we don't talk about unit cells in hcp/fcc structures?
I'm studying basics of Solid State Chemistry from this source.
So there are 14 types of Bravais crystal lattices (Primitive + Centered) in 3D. Every solid in this universe is made by the unit cells ...
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Phases in iron carbon diagram
The definition of phase :
Uniform chemical and physical composition.
So Alpha iron (0.001% carbon) and alpha iron (0.002% carbon) are two different phases??
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How many tetrahedral and octahedral holes are there in a bcc unit cell?
When I tried to count, I found 24 tetrahedral holes (each formed by 2 body centers of 2 unit cells sharing a face and 2 vertices of the same edge of that face). As each hole is being shared by 2 unit ...
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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 is solid titanium(II) oxide an electrical conductor?
Most salts in the solid state are electrical insulators, since the ions are not mobile (e.g. sodium chloride). However, solid titanium(II) oxide, $\ce{TiO (s)}$, is a conductor. How is this so?
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Can a solid be both crystalline and amorphous? [closed]
The first line in the Wikipedia article for "Glass" reads:
Glass is a non-crystalline amorphous solid that is often transparent and has widespread practical, technological, and decorative ...
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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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How would the crystal structure of sodium stearate look like?
In my lessons of solid state, I was taught about Bravais Lattices, and Face Centered, Body Centered, and Primitive cubic lattices, to name a few. All these crystal structures had this assumption, that ...
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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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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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What is the definition of porous materials?
Is there a consensus on scientific definition of porous materials? There are many definitions out there which do not seem accurate enough:
from wikipedia (accessed July 2017):
A porous medium or a ...
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Number of atoms per unit cell
I don't understand the concept of unit cell and the number of atoms per unit cell in a cubic lattice also the calculations for the number of atoms. For example in the $\ce{fcc}$ lattice, number of ...
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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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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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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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Band structure in half-metals
In a typical band diagram of a half-metal, the band structures for electrons of up and down spin are different. Why is this so?
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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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What are some materials that expand a lot proportionally to heat?
There's never any source on the internet that can simply give me a list of materials that have the kinds of properties I'm looking for. I'm wondering what materials, like for a solid block of ...
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In atomic diffusion in Au/Cu metal contact, where do the atoms come from ? (need melting temperature to break bonding in lattice ?)
It is known that Au metal is diffused when it is contacted with copper metal. And Au metal have lattice which consist of atoms. If so, may I think that atom is diassociated from lattice by heating ? ...
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Please help regarding finding the correct approach {solid states}
In Diamond, carbon atom occupy FCC lattice points as well as alternate tetrahedral voids. If edge length of unit cell is 356 pm then diameter of carbon atom is ________?
I got the answer but is it ...
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Is there an explanation to the atomisation energy trend of transition metals?
I am familiar with the double hump trend for atomisation of transition metals, and I can explain the unusually low atomisation of $\ce{Mn}$ with the exchange principle, specifically that in the solid ...
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Schottky Defect in AB2 type crystals
Are there any examples of Schottky defect in ${\ce{AB_2}} $ type crystals.
Does Schottky defect require that the cation and anion be of equal size?
According to me it is not necessary that the two ...
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Limiting radius ratio
I recently came across this question while studying Solid State.
The coordination no. of [Ni(CN)4]2- is 4 as Ni is bonded to 4 CNs and is planar in structure.Hence its Limiting Radius Ratio must be ...
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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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Chemistry of solids: allowed wavevectors
I'm a complete beginner in the chemistry of solids, and many of the things I came across don't make sense. I have two subquestions, which I think it would be most logical to post as a single question. ...
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Is it possible to determine the age of a building by just looking at its window?
I've recently come across the fact that glass is an amorphous solid and is known as a pseudo solid or a super cooled liquid. Our teacher told us that buildings that if we were to closely observe the ...
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Solid state and packing
In NaCl there is a simple cubic unit cell and the coordination number is 6. So i am confused how are both the ions arranged in such a lattice, with such a cordination no as in simple cubic unit cell ...
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what is meant by stability and potential energy of molecules in cases of formation of bonds?
molecules form chemical bonds in order to gain stability. it is said that forming bonds leads to lower potential energy of molecules and makes them stable. what does stability mean?
how formation of ...
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