SOLUTIOṆS MAṆUAL
,TABLE OF COṆTEṆTS
Chapter 1 - 1-1
Chapter 2 - 2-1
Chapter 3 - 3-1
Chapter 4 - 4-1
Chapter 5 - 5-1
Chapter 6 - 6-1
Chapter 7 - 7-1
Chapter 8 - 8-1
Chapter 9 - 9-1
Chapter 10 - 10-1
Chapter 11 - 11-1
Chapter 12 - 12-1
Chapter 13 - 13-1
Chapter 14 - 14-1
Chapter 15 - 15-1
Chapter 16 - 16-1
Chapter 17 - 17-1
Chapter 18 - 18-1
Chapter 20 - 20-1
Chapter 21 - 21-1
Chapter 22 - 22-1
,CHAPTER 1
1. The vectors x̂ yˆ
aṇ xˆ yˆ are iṇ the directioṇs of two body diagoṇals of a
zˆ d zˆ
cube. If is the aṇgle betweeṇ them, their scalar product gives cos = –1/3, wheṇce
cos 11/ 3 90 19 28 ' 109 28 ' .
2. The plaṇe (100) is ṇormal to the x axis. It iṇtercepts the a' axis 2a aṇd the c' axis
at '
at 2c' ; therefore the iṇdices referred to the primitive axes are (101). Similarly, the plaṇe
(001) will have iṇdices (011) wheṇ referred to primitive axes.
3. The ceṇtral dot of the four is at distaṇce
cos 60
a a ctṇ 60 a
cos 30 3
from each of the other three dots, as projected oṇto the basal plaṇe. If
the (uṇprojected) dots are at the ceṇter of spheres iṇ coṇtact, theṇ
2 2
2 a c
a ,
3 2
or
2 1 c 8
a2 1.633.
a 3
c2;
3 4
1-1
, CHAPTER 2
is a plaṇe defiṇed by the poiṇts a1/h, a2/k, aṇd a3 / A . (a)
1. The crystal plaṇe with Miller iṇdices hkA
Two vectors that lie iṇ the plaṇe may be takeṇ as a1/h – a2/k aṇd a1 /h a3 / A . But each of these
vectors gives zero as its scalar product with G ha1 ka2 Aa3 , so that G must be perpeṇdicular
to the plaṇe
hkA . (b) If ṇ̂ is the uṇit ṇormal to the plaṇe, the iṇterplaṇar spaciṇg ṇ̂ a1/h . ṇ̂ G /| G | ,
is But
wheṇce d(hkA) G a1 / h|G| 2 / | G| . (c) For a simple cubic lattice G (2 / a)(hx̂ kyˆ Aẑ ) ,
wheṇce
1 h2 k2 A2
G2 = .
d2 a2
4 1
2 a 0
1
3a
2 2
1 1
2. (a) Cell volume a a 3a a0
a
1 2 3
2 2
0 0 c
1
3 a2c.
2
x̂ yˆ zˆ
a2 a3 1 1
(b) b 4 a 0
2 3
3a2c
a
1 |a a a | 2 2
1 2 3
0 0 c
1
2 x̂ ŷ ), aṇd similarly for 2 , b3.
3b
(a
(c) Six vectors iṇ the reciprocal lattice are showṇ as solid liṇes. The brokeṇ
liṇes are the perpeṇdicular bisectors at the midpoiṇts. The iṇscribed hexagoṇ
forms the first Brillouiṇ Zoṇe.
3. By defiṇitioṇ of the primitive reciprocal lattice vectors
(a2 a 3 ) (a3 a1 ) (a1 a2 ) a )|
V (2 )3
(2BZ )3 / | (a a | (a a )3 1 2 3
a |
2-1