We changed our privacy policy. Read more.

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.

Filter by
Sorted by
Tagged with
3
votes
0answers
28 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{...
0
votes
0answers
60 views

Determine anion radius in FCC cell

The edge length of an FCC cell is $\pu{508 pm}$. If radius of cation is $\pu{110 pm}$, the radius of anion is? My approach: $$(2R_{\text{cation}}+2R_{\text{anion}})^2=2a^2$$ Which on simplification ...
0
votes
1answer
20 views

Adsorption on solids - homogeneous/heterogeneous surface definition

How could we define homogeneous and heterogeneous surfaces (rigorously)? It is among my exam questions (but I could not find any definition in my textbook or on the internet). I would say the ...
-4
votes
0answers
46 views

How does caesium triiodide exists?

How does $\ce{CsI3}$ exists? Means it contains $\ce{Cs+}$ and $\ce{I3^{-}}$ ions or $\ce{Cs+}$, $\ce{I-}$ and lattice $\ce{I2}$ Molecule? I was confused at this question? Can anyone help me which will ...
2
votes
1answer
52 views

What is the maximum length of peptide which considered to be hard for synthesis by the current technology?

I am a molecular biologist and work with recombinant proteins. I am wondering what the cut point, in terms of length, is at which I should produce the peptide using heterologous expression rather than ...
-1
votes
1answer
76 views

How many 4th nearest neighbours are there in an hcp lattice?

My teacher told us that there are 18 4th nearest neighbors in an hcp lattice, at a distance of √3a . I have only been able to identify 12. Can you help me find all the 4th nearest neighbors?
0
votes
0answers
28 views

Why do we have to use octahedral voids for formula making in solid state chemistry?

Allow me to take an example to explain myself. Q) What is the formula of a compound in which the element Y forms a ccp lattice and an atom of X occupy ${1\over3}$rd of tetrahedral voids? Now to find ...
6
votes
0answers
68 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{(...
2
votes
1answer
68 views

Understanding packing in different dimensions

In one dimension, there is only one way of packing, that is keeping the balls next to each other. In two dimension, we can keep a line of spheres on top of another line directly or we can keep the ...
1
vote
1answer
120 views

Radius ratio of octahedral interstitial site in BCC lithium

Problem Determine the minimum radius of an atom that will just fit into (a) the tetrahedral interstitial site in FCC nickel and (b) the octahedral interstitial site in BCC lithium. Solution (a) For ...
2
votes
0answers
91 views

Why is Cu2o[Copper(I) oxide] a (p-type)semiconductor?

Statement: Cu2O[Copper(I) oxide or cuprous oxide] is an extrinsic (p-type) semiconductor. Main Question: But why is Cu2O an extrinsic (p-type) semiconductor? My confusion: I understand how Silicone ...
1
vote
0answers
30 views

HCP and hexagonal primitive cell [duplicate]

There are 14 types of Bravais lattices one of them is hexagonal which is just present as primitive cell ie the basis are at its corners , now when I read about hexagonal closed packing I came to know ...
7
votes
1answer
45 views

In solid-phase peptide synthesis, why are the formation of aspartimides a problem but not "glutamides"?

I'm studying solid-phase peptide synthesis (SPPS) at the moment, and a common problem is the formation of aspartimides, which disrupt the synthetic process. I understand how they form and why are they ...
8
votes
2answers
517 views

Why are there exactly 5 types of two-dimensional lattices, and what distinguishes them?

In the book Chemistry: The Central Science, they introduced the following 5 types of two-dimensional lattices: The book said that the blue square represents the unit cell, the black dots are lattice ...
4
votes
0answers
42 views

Bond formations in doping of semiconductors [duplicate]

I was reading about semiconductors and found out that semiconductors are doped with either 13th group or 15th group elements which are named p-type and n-type semiconductors, respectively. In n-type ...
1
vote
0answers
34 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 ...
3
votes
1answer
56 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 ...
6
votes
3answers
1k views

Why is sea salt coarse?

What makes sea salt coarser than other salt? I have tried checking online but no one seems to discuss this. It seems that the grain of sea salt is larger, but I don't understand since the salt is ...
2
votes
0answers
45 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, ...
0
votes
0answers
61 views

Unit cell of hcp structure

It is given in my book that the structure in figure-1 is the unit cell of hcp structure. So why then is the structure in figure-2 not the unit cell as we can repeat the structure in figure-2 to get ...
2
votes
1answer
73 views

Why is the disordered CuAu structure more stable at high temperatures?

I know that the disordered CuAu structure is based around FCC whereas the ordered CuAu structure is tetragonal. Why would the FCC structure be more stable at high temperatures? For context, I was ...
4
votes
1answer
100 views

Getting an “index” of 7 for a set of powder diffraction data

I tried to index powder diffractogram from the following problem: A metal (of density $\pu{0.862 g cm^-3})$ gives the following powder X-ray diffraction data $(\lambda = \pu{1.5418 Å}).$ $$2\theta \...
-3
votes
2answers
410 views

Coordination number of 3D close packing [closed]

Can anyone explain me that how the coordination number of corner sphere of this 3-D packing is 6 ? it should be 3
0
votes
0answers
31 views

How many types of 3D packing are possible?

In my book it's said that there are 3 types of unit cubic cell - primitive , face and body centered . But for 3d packing types they have only mentioned FCC and HCP . I know that these 2 concepts- ...
2
votes
1answer
101 views

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 ...
1
vote
0answers
47 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 ...
0
votes
1answer
95 views

Height of CCP Lattice

Are the height of the Cubic Close packing Lattice and the cubic Hexagonal Close Packing the same? My understanding says that these unit cells are formed by different arrangement of atoms, ABC for CCP ...
4
votes
0answers
75 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 ...
0
votes
0answers
21 views

Degenerate semiconductors /N type dopants/Low fermi level

In extrinsic semiconductors the donor level of some N type dopants is lower in energy than some other dopants . For example as we move from the V to the VIII group if we draw the band diagram the ...
1
vote
1answer
613 views

How is Gibbs free energy related to stability? [closed]

I have been learning thermodynamics for quite some time and I fail to relate Gibbs free energy and stability. For example, how do I compare stability of metal oxides using the following data? Also, do ...
0
votes
0answers
39 views

Interatomic spacing vs electric conductivity

I have a theory which may be wrong but I will write it down.If 2 elements at the same group (in solids)have the same crystal structure then the one with the biggest interatomic spacing has better ...
1
vote
0answers
25 views

Clarification of term symbol explanation of laser crystal doping from textbook

I am currently studying Diode Lasers and Photonic Integrated Circuits, second edition, by Coldren, Corzine, and Mashanovitch. In chapter 1.2 ENERGY LEVELS AND BANDS IN SOLIDS, the authors say the ...
2
votes
2answers
422 views

Silicon–Boron Covalent Bond

This is a semiconductor-related question, but in order to understand the acceptor level energy state of boron in bilicon, I figured I'd ask here for hints. Boron is a p-type material when introduced ...
0
votes
1answer
132 views

Is the lattice point in ZnO crystal structure occupied by the molecule ZnO or the ion O^2-/Zn^2+?

I learnt that ZnO has a hexagonal crystal system. I was expecting that cations or anions would occupy the lattice points in hcp while voids would be occupied by anions or cations respectively. But ...
0
votes
1answer
97 views

What is the form of the Hamiltonian for solids?

For atoms, and even molecules, I can understand how the Hamiltonian would be constructed, but what of solids (as in, for electronic structure calculations)? Thank you for any help.
1
vote
1answer
67 views

Interplanar distance given Miller indice of the planes

Say we've a cubic crystal of unity edge length. A set of planes in such a crystal is specified by their miller indice as $(3 2 0)$. One of these planes then has intercepts on the axes as $(2 ,3 ,\...
1
vote
0answers
41 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+ ...
0
votes
0answers
37 views

Where are the tetrahedral voids and octahedral voids located in an FCC? [duplicate]

A crystal is made up of atoms X, Y, and Z. Atoms X are in FCC packing, Y occupy all octahedral voids and Z occupies all the tetrahedral voids. If all the atoms along two body diagonal are removed, ...
-3
votes
1answer
92 views

Ice geometrical shapes [duplicate]

https://en.wikipedia.org/wiki/Ice https://www.google.com/search?q=ice&prmd=inmv&sxsrf=ALeKk028fJvrUcWLWu8EV-KsRGuiw0iWWw:1596098668929&source=lnms&tbm=isch&sa=X&ved=...
1
vote
3answers
145 views

Why water cools from outside to inside?

It is a well-known fact that Water kept in a container, on cooling, results in freezing with initially at the circumference of surface (1D), then on the surface (2D) and then throughout the volume (...
0
votes
0answers
37 views

"e and a" as combinations of pi bonds

I am trying to get a better intuition on solid-state physics but I am a chemist by degree. I came across this article that attempts to bridge the gap between solid-state physics and molecular ...
5
votes
0answers
98 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 ...
0
votes
1answer
28 views

Doping of a solid with impurities [closed]

This question is a continuation of the previous question of mine:press me if you wish And my question is how can I dope a solid with impurities and if the process can be understood with basic ...
0
votes
2answers
196 views

How to identify if a material is perovskite or not?

This is more of a materials science question, but I believe many of you have referred NIST Inorganic Crystal Structure Database (ICSD) database. I am collecting a database of perovskite materials and ...
-1
votes
1answer
293 views

Are HCP and Primitive Hexagonal Unit Cell the same thing? [closed]

In HCP, the [2D] Hexagonal packed layers are arranged in ABAB form. The same happens in Primitive Hexagonal Unit Cell. So does that mean they are the same? If not what differentiates one from the ...
1
vote
2answers
343 views

Why rutile structure have primitive unit cell instead of body centered?

In the literature (Wikipedia), I read that $\ce{MgH2}$ have a structure of rutile. Then, I looked at its space group which is $P4_2/mnm$. From this notation, I understood that it possesses a (...
0
votes
0answers
41 views

Do all metals expand on heating? [duplicate]

This question came up when I was reading about substances with negative thermal expansion. The article by Takenaka [1] gives a good list of materials displaying negative thermal expansion. I noticed ...
0
votes
0answers
57 views

How can fluorite structure exist?

From the information from Google the radius of $\ce{Ca^2+}$ cation is $100 \,\pu{pm}$ and of $\ce{F-}$ anion is $132\, \pu{pm}$, so essentially $\ce{F-}$ ion should form the Bravais lattice (FCC/CCP) ...
-3
votes
2answers
197 views

Change in the number of ions due to exchanging ions [closed]

If the position of Na+ and Cl- are interchanged in NaCl having FCC arrangement of Cl- ions then what change we can observe in the unit cell of NaCl. I am confused as how the contribution will change ...
-1
votes
1answer
7k views

Calculate third and fourth nearest neighbours in fcc packing [closed]

My textbook has given data for third and fourth nearest neighbours to be 6 and 8 with distances  a and √(3/2)a. I have been able to calculate for the first and second nearest neighbour but it has ...

1
2 3 4 5
7