Homework. Exercises: 2-6, 9, 12, 14-18. Problems: 6, 7, 9, 11, 13, 14
Given a lattice, sketch a unit cell.
Recognize different types of centering.
Make a three-dimensional sketch of the rock salt structure.
Determine the number of atoms belonging to a given unit cell.
Given a three dimensional model of a unit cell, sketch a projection diagram, and vice versa. Exercises: 2
Describe the difference between the two closest packed lattices, hcp and fcc. Exercises: 3
Given a model of a common crystal structure type, describe it in terms of a lattice, and holes, and coordination numbers. Exercises: 4, 5
Identify the locations of holes in a close-packed structure.
Know the relative number of holes.
Describe two non-close-packed structures.
Describe (qualitatively) what happens to metallic (and ionic) radii when the coordination number increases (or decreases). Exercises: 6
Describe the two main types of alloys.
Predict whether a substitutional or interstitial alloy will result when two given elements are combined.
Given a structure, describe it in terms of a lattice type and holes.
Given ionic radii, calculate the radius ratio, ρ, of a binary compound, and predict which type of structure the compound will have by using a “radius ratio” table. Exercises: 10, 13
Given the enthalpy changes of all but one step, determine the missing enthalpy change using a Born-Haber cycle. Exercises: 15
Given ionic radii, calculate the lattice energy of a binary ionic compound. (Madelung constants, and other constants will be given.)
Arrange simple ionic compounds in order of increasing lattice energy based on charge and size. Exercises: 19
Sketch a large cation and a large anion.
Predict which of several compounds would be most soluble in water based on the relative sizes of the cation and anion. Exercises: 18
Account for variation in conductivity with temperature in metals.
Explain what a band is.
Describe how density of states (DOS) varies through a band in three-dimensional materials.
Use the concept of the Fermi energy distribution to explain how an intrinsic semiconductor conducts at room temperature.
Sketch the band structure of a p- and an n-type extrinsic semiconductor. Explain how these materials conduct as the temperature is raised.
Recognize the five basic symmetry operations. Exercises: 1, 2, 4.
Given the point group flow chart and a molecule, determine which point group the molecule belongs to. Exercises: 3. Problems: 1
Determine the degeneracy of a representation from its symmetry label.
Determine the representation that an atomic orbital belongs to from a character table.
Use symmetry to determine if a molecule is polar, and along which axis it is polar.
Use symmetry to determine if a molecule is chiral. Problems: 2, 3
Construct simple symmetry-adapted linear combinations of atomic orbitals.
Use a character table to label symmetry-adapted linear combinations of atomic orbitals.
Use a character table to determine which orbitals can mix. Exercises: 6, 7.