Crystals Definition and 132 Threads

Hello every one :) Actually i was studying from Charles Kittel ( introduction to solid state physics ) about crystals of inert gases , then i asked my self how could inert gases forms a crystals , i couldn't answer that , and no place to read about it :( . So can you people...

If you induce a shock wave in a covalent crystal using an ultrashort laser pulse, is there any way to estimate the temperature rise in relation to the pressure? Say I want to induce pressures of 10's of GPa. Is there a general way to think of this problem? I know next to nothing about shock...

Hi, I am having trouble understanding some things about k-space or momentum space in a crystal. The trouble began when I was first introduced to the Bloch theorem, a few weeks back. It is: \psi_{n\mathbf{k}}(\mathbf{r})=e^{i\mathbf{k}\cdot\mathbf{r}}u_{n\mathbf{k}}(\mathbf{r}). In...

Hi When talking about crystals, then what is a "conventional cell"? I know what a primitive cell is, but not what a conventional cell is. E.g. see this: http://www.scribd.com/doc/91701/Crystal-Lattices Here they do not describe a conventional cell, but just mention the name.

https://www.youtube.com/watch?v=_S1ZiNCz6CA In this video, the chief researcher is shown collecting a water sample from a very beautiful location in Japan. He takes it back to the lab, and divides the sample into 50 petri dishes. The amount of water in each petri dish is 1 ml. He then freezes...

is that at equilibrium, energy,U=0 from the equation below? U(R) = −(A /R6 )+ (B/R12 ) i nid to differentiate the equation and equate U=0?

In organic lab this week we were mixing (1-R, 2-S) ephedrine with mandelic acid to get crystals. I dissolved both compounds in 6 mL 95% EtOH and then poured them together. After cooling + glass prodding I should have had no trouble getting crystals. HOWEVER, during the cooling I accidently...

I'm not sure where this question belongs, maybe in chemistry? move it if necessary. so the quest is this I have a salt crystal lamp. it is a large block of salt on a wood base with a light bulb inside a hollow in the salt. the selling point of these lamps is that the heat from the...

When it comes to the piezoelectric effect you can have a small quartz crystal and apply a force to it and get thousands of volts as a result. But if you took a quartz crystal and applied a thousand volts to it, would it just crack? For a quartz crystal to take a couple thousand volts charge (no...

In order to study the structure of crystals, scientists normally use X-rays. Why do they use X-rays and not visible light? I'm thinking it has something to do with wavelengths, but I do not know why the difference of wavelenght matters.

[Xray reflection 1. Homework Statement X-rays of 1.54 angstroms are reflected off copper powder @ 21.65º 25.21º 37.06º 44.96º 47.58º Find the cubic lattice and the length of an edge of the unit cell. 2. Homework Equations nλ = 2d sin(Θ) ; the Bragg equation 3. The...

I have two different types of questions regarding crystals and clocks. I can't remember if I've asked these question before. I'd appreciate any input on this topic. Crystal external circuitry: Almost any IC with an external crystal has two pins to connect to it. Now my question is how...

I'm stuck with a problem of finding the minimum energy of an inorganic crystal. Crystal is of monoclinic structure with 18 parameters to specify its internal coordinates and 2 atomic species. Am using a classical interatomic potential found in literature. The minimization involves both the...

Yoy guys, I am working on an invention recently which is related to liquid crystals. I want to know how liquid crystals in a forehead thermometer works. Or basically, how a forehead thermometer works! Thx guys!

I wanted to ask if a continuous pressure on a piezoelectric produce a continuous potential or not??if not why??

I thought optical phonons only existed in crystals with two or more types of atoms in a unit cell. But I keep reading references of optical phonons in single atom crystals, like silicon. What's the deal here?

First i want to say hello, since i am new here. ok, I don't know tons about physics, so the following is an idea that i have, and would like to know if it was possible. my idea is: Why not use a laser to write 0's and 1's inside a glass or stone crystal? we can already use such lasers...

Hi, You can be sure that the method that I'm going to propose is of no commercial significance. Anyway, I'd like to know why. Set up(regardless of dimensions):- place two permanent magnets with like their like poles closest to each other in a linear tube and at the end of the tube...

Not sure if this is right place to be asking-here goes: Am a video art student and am interested in capturing crystals in liquid- Have noticed crystal formation in some semi freezing oil which visually is pretty interesting! Really not knowledgeable in the field of chemistry / physics...

Homework Statement Which two of the following could be used to produce crystals of nickel? A Addition of a piece of copper to a NiSO4 B Addition of a piece of zinc to a NiSO4 solution. C Addition of a piece of potassium to a NiSO4 solution. D Electrolysis of molten NiSO4. Homework Equations...

can someone explain to me how sundogs form? I know it has to do with refraction of light through ice crystals but i need a good ray diagram explaining this...

What is the shape of salt crystals.??

Hello, sorry to bother again but I've been giving this much thought as well and am very confused.. Please refer to the following page: http://x5.freeshare.us/119fs641427.jpg If I am supposed to calculate the direction vector for the hexagonal crystal, I was told to: 1) Calculate the...

I'm working on a lab report on powder X-ray diffraction off of some relatively straight-forward crystals (Si, NaCl, CsCl) for an introductary course on modern physics. I thought it would be useful to include a partial derivation of the formula relating the distance between parallel planes, d...

http://arxiv.org/abs/gr-qc/0509091 A liquid crystal analogue of the cosmic string "We consider the propagation of light in a anisotropic medium with a topological line defect in the realm of geometrical optics. It is shown that the effective geometry perceived by light propagating in such...

I am in search of physical properties of inert gas crystals ( such as colour,lustre,etc). I could get only the melting point. Specifically, i want for Neon, Argon, Krypton and Xenon which are fcc.

from C.Z. Tan, Optical interference in overtones and combination bands in \alpha-quartz, Journal of Physics and Chemistry of Solids 64 (2003) 121–125. [1] M. Born, K. Huang, Dynamical Theory of Crystal Lattices, Clarendon Press, Oxford, 1988. [2] C. Kittel, Introduction to Solid State...

Hi, I would like good information about photonic crystals. Does anyone know where to find this? I would like the text to begin at the basic concepts. The only Solid stat physics book i have is "Introduction to solid state physics" 7th Edition by Kittel and it doesn´t say much about this...

I need some help here guys. I'm looking at three books about gems and crystals and I want to see what y'all recommend. The three are the following: Stones Alive! by Trintress, The Crystal Bible by Judy Hall, and Healing Crystals by Cassandra Eason. Keep in mind, guys, that I'm just a beginner...

Shock waves propagating in photonic crystals can be used to lower or raise the frequency of light passing through them. It seems (to me) to be some kind of Doppler effect at work here. The electrons in the atoms of the crystal absorb the light, and as they move because of the propagating...

This is an interesting new development.

Was going to put this up a couple of days ago but was a bit preoccupied. So here goes. Imagine that you take a single crystal of Iron, a whisker, and bend it around to make a circle. How could you find out if the crystal was magnetized? Remember, all the magnetic field is contained inside the...