Answers to PS #1 - Classes at U. of L.

14. Using the data in Table 1.2 in Smart and Moore and the formulae in the Introduction to the Lecture Notes, calculate the
volumes of the following (primitive) unit cells in the seven crystal systems:
a) Cubic, a = 3.4Å b) Tetragonal, a = 4.0 Å, c = 2.5 Å
c) Orthorhombic, a = 2.3, b = 2.7, c = 1.9 Å d) Hexagonal, a = 3.4, c = 1.8 Å
e) Trigonal-b a = 2.1 Å, a = 87 f) Monoclinic, a = 1.7, b = 2.2, c = 5.3 Å; β = 109°
g) Triclinic, a = 2.4, b = 2.6, c = 4.1 Å; a = 92, β = 98, γ = 103°
15. Express the location of the ligands L of the following ELn molecules as x,y,z coordinates, with E at 0,0,0. Use
symmetry operators to simplify your work, and state explicitly how you have used symmetry.
a) CH4, d(C-H) = 1.10 Å tetrahedral b) PtCl4 2- , d(Pt-Cl) = 2.30 Å sq. planar
c) NH3, d(N-H) = 1.08 Å, ∠(H-N-H) = 106° pyramidal d) H2O, d(O-H) = 1.06 Å, ∠(H-O-H) = 104° bent
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