Structure of Materials

Question 1

Define macrostructure

Answer 1

: structure as examined with the naked eye or
under low magnification (may itself include different levels of structure)

Question 2

Define microstructure

Answer 2

structure as observed using optical microscopy

Question 3

define substructure

Answer 3

structure obtained by using a microscope with
a much higher magnification and resolution than the optical microscope (i.e. scanning electron microscopy)

Question 4

describe crystal structure

Answer 4

atoms situated in an orderly, repetitive
arrangement which occupies space.
Provides the details of the atomic arrangement within a cell.
Usually sufficient to describe the arrangement of a few atoms within what is called a unit cell

Question 5

describe electronic structure

Answer 5

electrons in the outermost orbitals of
individual atoms that constitute the solid. Spectroscopic techniques are very useful in
determining electronic structure

Question 6

Nuclear structure

Answer 6

studied by nuclear spectroscopic
techniques, such as nuclear magnetic resonance (NMR)

Question 7

molecular structure

Answer 7

spatial arrangement of small groups of atoms which are strongly joined together within the group or molecule

Question 8

What is the deformation behavior of a material? how is it affected?

Answer 8

its response to applied loads and forces
strongly affected by molecular and crystal structure

Question 9

describe what is an isomer

Answer 9

if the atoms in a molecule have the capability of
forming different geometrical or structural arrangements without a change in chemical composition

Question 10

describe polymorphism

Answer 10

In a crystalline material, the ability to transform from one type of geometrical configuration to another

Question 11

describe a perfect structure

Answer 11

means that no atoms or ions are missing from their appointed positions and that the respective structure exhibits no geometrical deviations from perfection