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S.No. Properties Diamond cube(dc) Simple Cube(sc) Body CenteredCube(bcc) Face Centered Cube(fcc) Hexa-gonalClose_pack structure NaCl
1 Vol.of unit cell a^3 a^3 a^3 a^3 (3/2) [√3(ca^2)] a^3
2 No. of atoms percell 8 1 2 4 6 4 cations4 anions
3 No.of atoms per unit vol. 8/ a^3 1/ a^3 2/ a^3 4/ a^3 4/ [√3(ca^2)] 8/a^3
4 No.of nearest neighbours 4 6 8 12 12
5 Nearest neighbourDistance(2r) a√3/4 a/2 a√3/2 a√2/2 a/2
6 Atomic radius a√3/8 a/2 a√3/4 a√2/4 a/2
7 Atomic packingFactor π√3/16=0.34 π/6= 0.52 π√3/8=0.68 π √2/6=0.74 π√2/6=0.74 0.67
8 Examples Ge, Si and Diamond Polonium Sodium,Iron,Chromium Aluminium,Copper,Lead Magnesium,Zinc,Cadmium Ionic solids such as NaCl, AgCl,LiFMgO,CaO

Water shows an anomaly in the range from 4°C to 0°C. With reduction in temperature at and below 4°C the density decreases instead of increasing. At 0°C, the Ice Temperature, it has the lightest density. This is because of the open-pack hexagonal structure of ice crystal. From 4°C to 0°C, the phase transition is occurring through out the volume of liquid and at 0°C the phase transition is complete. At this temperature the whole mass of water is fully transformed into a solid piece of ice. Therefore at 0°C we have the lightest density of Ice. It is this anomaly which helps the survival of fishes in frozen lakes. Nine-tenth of ice-berg is submerged and one-tenth of the ice-berg is visible. Therefore we say that the tip of the ice-berg is visible.

1.11.2 ALLOTROPIC FORMS OF CARBON

There are elements which exist as different crystalline allotropes such as Carbon. This most commonly found element exists as three crystalline allotropes namely Graphite, Diamond and Buckminstefullerene Crystal also known a buckeyball structure. The structure is shown in Figure 1.56 and Figure 1.57 and their properties are tabulated in Table (1.22).

1.11.2.1. DIAMOND CRYSTAL.

In Figure 1.56 we show the Diamond allotropic form of Carbon. As shown in Fig 1.56 A , Diamond is two interpenetrating FCC sub-lattices with one sub-lattice displaced with respect to the other along the diagonal of the cube by a quarter of diagonal length (a√3)/4 where ‘a’ the lattice parameter. Since Diamond unit cell is a cube, its lattice parameter is the side of a cube as shown in Figure 1.56 B. The basic unit cell of Diamond is cube of equal sides ‘a’ length. ‘a’ is the lattice constant of Diamond. Its value is 3.57 Angstrom. The basic unit cell is subdivided into 8 subcubes ABCDEFGH. ABCD comprise the upper 4 subcubes and EFGH comprise the lower 4 subcubes. In the Figure 1.56B , subcube E is hidden due to the perspective view. The subcube A, C, in the upper layer and F,H in the lower layer contain the tetrahedral structure of carbon atoms as shown in Figure 1.56D. As a result the basic UNIT CELL has 8 C atoms at the 8 corners of the cube, 6 C atoms on the six faces of the cube and 4 C atoms in the bodies of A, C , F, H subcube. The net result is that on looking at the PLAN VIEW of Diamond Unit Cell as shown in Figure 1.56C we see one C atom sharing its 4 valence electrons with 4 C atoms at its 4 corners. This kind of structure is repeated through out.

Questions & Answers

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
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
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Solid state physics and devices-the harbinger of third wave of civilization. OpenStax CNX. Sep 15, 2014 Download for free at http://legacy.cnx.org/content/col11170/1.89
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