If you find the material in Chapters 2 and 18 confusing, you may also want to consult the following book: Callister, W. D. "Materials science and engineering. An introduction" 5th edition, Chapter 3. This book is available in the Chemistry library, reserved for Chem. 407B.
Chapter 4
Problems: 4.7 and 4.8
Exercises: 4.10 and 4.11
Give the point group for each molecule
and the symmetry elements leading to your answer:
a) B2H6
b) B6H6 2-
c) Ferrocene (staggered)
d) Si2O7 6- (staggered w/linear Si-O-Si)
e) Si2O7 6- (eclipsed)
f) Re2(OCR)4Cl2
g) Fe2(CO)9
h) Pt(PF3)4
i) PF5
j) CCl4
k) B2H7