<< Chapter < Page Chapter >> Page >

Solid state structures and superconductors

 Objectives

  • Build examples of: simple cubic, body centered cubic and face centered cubic cells.
  • Understand and familiarize with three-dimensionality of solid state structures.
  • Understand how binary ionic compounds (compounds made up of two different types of ions) pack in a crystal lattice.
  • Observe the special electromagnetic characteristics of superconducting materials using 1,2,3-superconductor YBa 2 Cu 3 O 8 size 12{ ital "YBa" rSub { size 8{2} } ital "Cu" rSub { size 8{3} } O rSub { size 8{8 - times } } } {} , discovered in 1986 by Dr. Paul Chu at the University of Houston.

Grading

Your grade will be determined according to the following

  • Pre-lab (10%)
  • Lab report form. (80%)
  • TA points (10%)

Before coming to lab:

  • Read introduction and model kits section
  • Complete prelab exercise

Introduction

From the three states of matter, the solid state is the one in which matter is highly condensed. In the solid state, when atoms, molecules or ions pack in a regular arrangement which can be repeated "infinitely" in three dimensions, a crystal is formed. A crystalline solid, therefore, possesses long-range order; its atoms, molecules, or ions occupy regular positions which repeat in three dimensions. On the other hand an amorphous solid does not possess any long-range order. Glass is an example of an amorphous solid. And even though amorphous solids have very interesting properties in their own right that differ from those of crystalline materials, we will not consider their structures in this laboratory exercise.

 

The simplest example of a crystal is table salt, or as we chemists know it, sodium chloride (NaCl). A crystal of sodium chloride is composed of sodium cations ( Na + size 12{ ital "Na" rSup { size 8{+{}} } } {} ) and chlorine anions ( Cl size 12{ ital "Cl" rSup { size 8{ - {}} } } {} ) that are arranged in a specific order and extend in three dimensions. The ions pack in a way that maximizes space and provides the right coordination for each atom (ion). Crystals are three dimensional, and in theory, the perfect crystal would be infinite. Therefore instead of having a molecular formula, crystals have an empirical formula based on stoichiometry. Crystalline structures are defined by a unit cell which is the smallest unit that contains the stoichiometry and the“spatial arrangement”of the whole crystal. Therefore a unit cell can be seen as the building block of a crystal.

 

 

 

The crystal lattice

 

In a crystal, the network of atoms, molecules, or ions is known as a crystal lattice or simply as a lattice. In reality, no crystal extends infinitely in three dimensions and the structure (and also properties) of the solid will vary at the surface (boundaries) of the crystal. However, the number of atoms located at the surface of a crystal is very small compared to the number of atoms in the interior of the crystal, and so, to a first approximation, we can ignore the variations at the surface for much of our discussion of crystals. Any location in a crystal lattice is known as a lattice point. Since the crystal lattice repeats in three dimensions, there will be an entire set of lattice points which are identical. That means that if you were able to make yourself small enough and stand at any such lattice point in the crystal lattice, you would not be able to tell which lattice point of the set you were at–the environment of a lattice point is identical to each correspondent lattice point throughout the crystal. Of course, you could move to a different site (a non-correspondent lattice point) which would look different. This would constitute a different lattice point. For example, when we examine the sodium chloride lattice later, you will notice that the environment of each sodium ion is identical. If you were to stand at any sodium ion and look around, you would see the same thing. If you stood at a chloride ion, you would see a different environment but that environment would be the same at every chloride ion. Thus, the sodium ion locations form one set of lattice points and the chloride ion locations form another set. However, lattice points not only exist in atom positions. We could easily define a set of lattice points at the midpoints between the sodium and chloride ions in the crystal lattice of sodium chloride.

Questions & Answers

Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
hi
Loga
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
Got questions? Join the online conversation and get instant answers!
Jobilize.com Reply

Get the best Algebra and trigonometry course in your pocket!





Source:  OpenStax, Gen chem lab. OpenStax CNX. Oct 12, 2009 Download for free at http://cnx.org/content/col10452/1.51
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Gen chem lab' conversation and receive update notifications?

Ask