Top Banner

of 47

Crystalography (1)

Feb 24, 2018

Download

Documents

Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
  • 7/25/2019 Crystalography (1)

    1/47

    2.1

    ,

    ,

    , ,

    , .

    .

    , ,

    . .. , ,

    . .

    , ..

    , .

    , ,

    ,

    ,

    . , ,

    ,

    .

    (. 2.1).

    . 2.1: ()

    .

    .

  • 7/25/2019 Crystalography (1)

    2/47

    46

    , .

    ,

    , :

    1) :

    ,

    .

    2) :

    , .

    :

    , .

    , ,

    :

    ,

    , .

    3) :

    ( )

    (), .

    4) :

    (,

    ).

    ,

    , . , , ().

  • 7/25/2019 Crystalography (1)

    3/47

    47

    (, )

    . ,

    .

    , .

    ,

    . ,

    ,

    ,

    , ,

    .

    ,

    . Hay, 1784,

    ,

    . , ,

    , (. 3 ). , ,

    , ,

    .. ,

    . Hay, ,

    ,

    .

    -

    , :

    , . ,

    , , ,

    ,

    .

    ,

    . ,

  • 7/25/2019 Crystalography (1)

    4/47

    48

    , .

    (. 2.2,).

    ( )

    . ,

    , . , (, m

    )

    -.

    . 2.2: -

    (m, ).

    . 2.2:

    -

    ( .)

    ,

    .

    ,

    .

    ,

    . , ,

    , .

    (. 2.3).

    .

    , ,

    .

    , . ,

    -,

    2/ .

    , 2.

    (. 2.4).

  • 7/25/2019 Crystalography (1)

    5/47

    49

    . 2.3: (i).

    .

    . 2.4: , 2, 3, 4

    6, .

    ,

    . ,

    56. ()

    () .

    ,

    1.

  • 7/25/2019 Crystalography (1)

    6/47

    50

    1: . (: 1, 2,

    3, 4, 6 ) ,

    .

    : 6.

    6

    2= 60

    : 4

    .

    4

    2= 90

    : 3.

    3

    2= 120

    : 2.

    2

    2= 180

  • 7/25/2019 Crystalography (1)

    7/47

    51

    (. 2.5). , , ,

    . , ..

    2,

    .

    . 2.5: 4 , 4 2

    , 5 (m).

    , ,

    ., -

    -

    ,

    ( ).

    ( ).

    , , ,

    ,

    .

    , (proper

    rotation),

    , (improper rotation).

    (1, 2, 3, 4, 6)

    (m). 1/m, 2/m, 3/m, 4/m

    6/m, . , 1

    (. 2.6), 2

    (. 2.6) , , 6 3/m.

    , 1 , 2 6

    .

  • 7/25/2019 Crystalography (1)

    8/47

    52

    () ()

    . 2.6: () 1( 1 ),

    360

    . () 2 (2) 180

    .

    (m) 2 .

    , ,

    ,

    .

    , . ,

    (low symmetry).

    , (high symmetry). ,

    : 6

    4,

    3... ,

    , .

    . 2.7: (

    ).

    , ,

    .

  • 7/25/2019 Crystalography (1)

    9/47

    53

    , , .

    4, 3, 2, (. 2.7)

    . , , ,

    .

    .

    .

    .

    , ,

    , .. , ,

    , , .

    , 6

    ,

    .

    ,

    ,

    , 32

    . 32

    (point group). .

    ,

    .

    , ,

    : .

    , .

    .

    , . ,

    , .

    (32 )

    . .

    32

    . ,

  • 7/25/2019 Crystalography (1)

    10/47

    54

    -,

    .

    , ,

    .

    , 1.

    -,

    , .

    - - .

    .

    ( ),

    x,y,z

    a, b, c (

    ) .

    . ..

    4

    . ,

    90

    z,

    x, a

    , y, b = a

    (. 2.8). , , xy.

    , , z,

    . c/a z

    x y, a/b = 1, . ,

    (a=bc)

    .

    . 2.8:

    (a, b = a,

    c)

    4(,

    z).

    .

    .

    1.

  • 7/25/2019 Crystalography (1)

    11/47

    55

    32 (, )

    , .

    .

    ,

    ,

    (. 2).

    1, , ,

    .

    .

    2:

    . 2,

    , . , ,

    - /3

    a, b, (a+b).

    1

    , . , .

  • 7/25/2019 Crystalography (1)

    12/47

    56

    32

    ,

    .

    ,

    -.

    .

    , ,

    ,

    ( ),

    () .

    , , ,

    .

    .

    , ,

    . :

    + = =

    , .

    .

    .

    , ,

    .

    (. 2.9).

    ,

    ,

    .

    ,

    , .

    ,

    . , ,

  • 7/25/2019 Crystalography (1)

    13/47

    57

    ,

    .

    () ()

    . 2.9: () () .

    ab.

    . , 5

    6

    . 2.10

    . (,

    ) , . ,

    . , ,

    , , .

  • 7/25/2019 Crystalography (1)

    14/47

    58

    . 2.10: . , ,

    2, 3, 4 6 ,

    . , .

  • 7/25/2019 Crystalography (1)

    15/47

    59

    ,

    1, T,

    a, b, c:

    T= n1a + n2b + n3c

    ni . ,

    abcab.

    () 2

    .

    ()

    rr:

    r= r + T= r+ n1a + n2b + n3c

    (r, r)

    ()

    r, n1, n2, n3.

    , a, b, c .

    (),

    , ni.

    ,

    . , a, b, c,

    , ,

    r, r

    n1,n2, n3(. . 2.11). ,

    ni,

    , .

    (.. ) a,

    b, c,. ,

    90,

    , .

    ,

    .

    1.2

  • 7/25/2019 Crystalography (1)

    16/47

    60

    . 2.11: c

    (n1,n2, n3) = (2, 3, 5). a, b,

    c .

    ,

    . ,

    . , ..,

    , , ,

    , (.

    , ).

    .

    , ()

    . ,

    , ,

    (unit cell).

    a, b, c

    (. 2.12).

    , . 1, (:

    primitive unit cell), .

    ,

    a

    (b

    c). . 2.13. , ,

    , .

    1. , . ()

    , 1/8 , .

  • 7/25/2019 Crystalography (1)

    17/47

    61

    . 2.12: . a, b, c

    a, b, c.

    , , .

    .

    . 2.13:

    (Primitive) (Non-Primitive) .

    (P) .

    .

    ,

    1

    , .

    . , (,

    .)

    .

    1, , . , , ,

    , .

  • 7/25/2019 Crystalography (1)

    18/47

    62

    BRAVAIS

    , 2,

    , ,

    , .

    .

    ,

    ,

    , , (

    32 ).

    (

    ).

    , ,

    .

    (centering)

    (.. 4 ,

    1.10).

    ,

    . ,

    ,

    1.

    .

    ,

    . ,

    :

    (face centered, F):

    .

    1

    . , . , ,

    (, ). - -.

  • 7/25/2019 Crystalography (1)

    19/47

    63

    (body centered, I):

    .

    - (side base end- centered, C):

    .

    .

    (.

    ).

    , ( )

    , .

    .

    Bravais. 3 . 2.14 ,

    ,

    ,

    .

  • 7/25/2019 Crystalography (1)

    20/47

    64

    3

    (,

    )

    ()

    ()

    (P, R)*

    (I, F, C)*

    ()

    a=b=c

    a===90

    4 3 P, I, F

    a=b

    ===90

    1 4 P, I

    ===90 3 2

    P, C, I, F

    a=b, ==90

    =120

    1 6

    P

    ()

    a=b=c

    ==90

  • 7/25/2019 Crystalography (1)

    21/47

  • 7/25/2019 Crystalography (1)

    22/47

    66

  • 7/25/2019 Crystalography (1)

    23/47

    67

    : )

    ) .

    ( ),

    , ,

    .

    (1/3a, 2/3b, 2/3c) (2/3a, 1/3b, 1/3c)

    a = b = c, = = 90

  • 7/25/2019 Crystalography (1)

    24/47

    68

    ,

    . , ,

    , . .

    ,

    , ,

    (P, I, F C) ,

    .

    3(3 3 ). , 4

    . 3

    ,

    2

    . , ,

    23.

    (), .

    , , :

    :

    4/m 3 2/m 1 432 4 3 m 2/m 3 2 3

    6

    3 (3 3 ) ,

    . 3 ( 3 ) .

    , , 2

    .

    . , :

    :

    6/m 2/m 2/m 622 6mm 6 2/m 6/m 6 6

    () :

    3 2/m 32 3m 3 3

    1

    Bravais, . , 23 (23P, 23I, 23F ). .

  • 7/25/2019 Crystalography (1)

    25/47

    69

    ( Hermann

    Mauguin), , ,

    , .

    ,

    , 4:

    4

    () 4, 4/m, 4 , 2, 2/m 3, 3 2, 2/m, m

    - 6, 6/m, 6 , 3, 3 2/m, m 2, 2/m, m

    4, 4/m, 4 2, 2/m, m 2, 2/m, m

    2, 2/m, m 2, 2/m, m 2, 2/m, m

    2, 2/m, m

    1, 1

    , ,

    , , (

    ). 3

    ,

    5444 (). , ,

    2

    , , 45

    (2 ). , 23

    2

    ( ) 3

    5444.

    ,

    (). ,

    , 2, 120

    ,

    120, .

    , , 2

    .

    . ,

    . ,

    , 4/m3 2/m,

    , .. . ,

    (crystal forms). ,

    ,

  • 7/25/2019 Crystalography (1)

    26/47

    70

    . , ,

    , , , .

    ( ) , .

    ,

    , , (

    4/m3 2/m). , ,

    . ,

    , (

    4 3m).

    . ,

    .

    , , ,

    .

    (-, , )

    ,

    .

    , .

  • 7/25/2019 Crystalography (1)

    27/47

    71

    -

    .

    (P, I, F, C),

    ,

    (.) Bravais.

    ,

    .

    , .

    , , .

    .

    , (Cu) Cu

    . Cu ,

    (

    ) ,

    ,

    . ,

    . ,

    .

    . , ,

    ,

    . , ,

    , - -

    . (. . 2.15 ).

    ( ) ,

    ,

    . ,

    ,

    (. 2.16). ,

    ,

    . , , , :

    ,

    ,

  • 7/25/2019 Crystalography (1)

    28/47

    72

    . . ,

    4 , , ,

    4

    (. . 2.10). 3

    6

    , , ,

    (. . 2.10). , 2

    ,

    , 2 (. 2.10),

    . , NaCl

    (. 2.17).

    . 2.15: , , 6mm.

    ,

    33 ()

    3m ( ).

    (6mm, 6, 3m, 3, 2mm, 2, 1m).

  • 7/25/2019 Crystalography (1)

    29/47

    73

    . 2.16: (),4

    (4mm),

    . (2mm)

    , (

    , ).

    . 2.17: NaCl

    (4mm), (.. Cl).

    , ,

    , , .

  • 7/25/2019 Crystalography (1)

    30/47

    74

    ,

    , ,

    32 ,

    . , 32

    , : 32

    .

    , , 32

    , 14 Bravais.

    (space

    groups). , 2/m .

    , P C, P2/m

    C2/m . , P4 ,

    4

    . , F4/m3 2/m

    ,

    .

    Bravais

    72 . , ,

    (-

    ),

    ,

    .

    .

    ,

    , ,

    (. 2.18, 2.19,

    2.20).

    -

    .

  • 7/25/2019 Crystalography (1)

    31/47

    75

    . 2.18: ) , ) (

    ) , )

    .

    . 2.19: , t,

    .

    , (/)

    (.. 31t/3 /3).

  • 7/25/2019 Crystalography (1)

    32/47

    76

    . 2.20: O

    () . PP

    .

    PP ty/2

    , PP .

    ,

    , . ,

    ().

    .

    .. ,

    , .

    ,

    . , , 1.18

    1.20 , ,

    ,

    . , ,

    . ,

    , ,

    . ,

    P4/m P42/m, 4/m.

  • 7/25/2019 Crystalography (1)

    33/47

    77

    ,

    (. ). , ,

    . , ..

    (. ),

    ,

    ,

    .

    ,

    , (. . 2.19)

    m.

    :

    1)

    2)

    3)

    4)()

    5)

    6)

    ()

    ,

    ,

    .

    ,

    , .

    ,

    ,

    . ,

    ,

    ,

    . , -

    ,

    . , 11

    .

  • 7/25/2019 Crystalography (1)

    34/47

    78

    1 14 Bravais

    230 ,

    . 230

    2. :

    ( ), 230 230

    , .

    , 17 , 17

    .

    230 .

    ,

    .

    .

    :

    )

    ,

    )

    .

    .

    .

    ,

    ,

    , .

    ,

    . ,

    Bravais

    ,

    .

    1 , 32 .2,

    32 . , Bravais . .. (. . 4)

    2

    . , 3, 3132.

  • 7/25/2019 Crystalography (1)

    35/47

    79

    -

    . , , ,

    -

    ,

    . ,

    .

    xyz

    ,

    : xa, yb, zc. ,

    , a, b, c,

    , (x, y, z),

    (. 2.21 & 2.23).

    1, ,

    . >1 < 0,

    , , . ,

    .

    , .. (2/3, 1/2, 7/8) (1/3, 1/2, 7/8).

    ,

    (x, y, z). ,

    1.

    (n1a + n2b + n3c, ni),

    (. 2.22).

    1

    : , , , . , , .

  • 7/25/2019 Crystalography (1)

    36/47

    80

    . 2.21: .

    ,

    , x

    .

    . 2.22: .

  • 7/25/2019 Crystalography (1)

    37/47

    81

    . 2.23: (

    z).

    .

    ,

    ,

    .

    , , .

    ,

    . ,

    , .

    ,

    ().

    , (x, y, z),

    192 , (x,

    y, z). , , , () , , 192 16.

  • 7/25/2019 Crystalography (1)

    38/47

    82

    ,

    , , , .. [hkl],

    (.

    224). : ,

    , ,

    .

    x, y, z, h, k, l,

    x, y, z,

    [(x/2, y/2, z/2), (2x, 2y, 2z), (3x, 3y, 3z) ...].

    .

    . 2.24: () ,

    OA =1a+3b+2c [132].

    () ab

    .

    () . 2.24.

    :

    - (1/2, 0, 1), (1, 0, 2),

    [102]. ,

    : 1a+0b+2c = a+2c

    xz.

  • 7/25/2019 Crystalography (1)

    39/47

    83

    - [3

    2 3

    1 1] [213]

    - (-1, 2, 0) ]201[ .

    . 2.24, [120] (OC) [240] (OD) . ,

    (.. , , ). . 2.24, a-b,

    [hk0]. ,

    0,

    (). ,

    , 0, . ,

    .. [010] b (. 2.25).

    . 2.25: .

    ,

    .

    . , , ,

    ,

    .

    , ,

    .

    .

  • 7/25/2019 Crystalography (1)

    40/47

    84

    :

    . , .. . ,

    , ,

    . -

    .

    , ,

    . ,

    .. [100], [010], [001] (,

    . . 2.25) 100 . ,

    ( ]111[ , ]111[ , ]111[ , ]111[ , .) 111 1.

    ,

    ,

    , , .. (hkl),

    Miller.

    Miller, () , :

    1)

    ,

    2)

    ,

    3) .

    , .. (210) (. . 2.26) a, b, c,

    , 1 (c). ,

    2, 1 0, Miller.

    , .. )( 221 . {}

    . , .. (100), (010), (001), )001( ,

    )010( )100( , ,

    {100}.

    1, . ,

    .. ]111[ ]111[ , ]100[ ]001[ , . (. . 2.25).

  • 7/25/2019 Crystalography (1)

    41/47

    85

    . 2.26:

    () .

    (hkl) ,

    ,

    (hkil), Miller-Bravais. ,

    , , i

    h k: (h+k = i). , ,

    .. (0110)

    (01.0) (010). , , [hkl]

    (hkl), ,

    .

    Miller

    .

    d, ,

    , . Bragg. , ,

  • 7/25/2019 Crystalography (1)

    42/47

    86

    (.. )

    ,

    / ,

    d.

    , ,

    .

    (, , , = =

    = 90), d ,

    Miller (hkl), :

    2

    2

    2

    2

    2

    2

    2hk cb

    k

    a

    h

    d

    1 l

    l

    ++= ,

    a, b, c (

    ).

    a = b ( ) a = b = c

    (). :

    2

    222

    2hk a

    kh

    d

    1 l

    l

    ++=

    a ,

    (hkl) , d .

    , :

    3da111

    =

    , :

    2

    222

    2

    hka

    )c

    a()khkh(

    3

    4

    d

    1 l

    l

    +++

    = .

    , , ..:0.11d2a= 2.00d2c=

  • 7/25/2019 Crystalography (1)

    43/47

    87

    d. , V , :

    2)d

    V( = h2b2 c2 2+ k2 a2 c22+ l

    2a2b22+

    + 2hl ab2 c(- )

    + 2hkabc2 (- )

    + 2kl a2bc(- ).

    :

    ( ). (.. )

    . , ,

    .

    , ,

    . ,

    . ,

    . , , Bravais,

    - . 2.27. ,

    .

    . 2.27:

    :

    1 2 3 4 5.

    , ,

    . , ..

    1/ 2 , 1 2/3, 2 , 1, 3/2 . ,

  • 7/25/2019 Crystalography (1)

    44/47

    88

    ().

    ,

    , ,

    . ,

    .

    , ,

    , . ,

    ,

    , /

    . , ,

    ,

    ,

    (. 2.28).

    . 2.28:

    {001} a - {111} o .

    .

  • 7/25/2019 Crystalography (1)

    45/47

    89

    , ,

    .

    . , ,

    , (. 2.29).

    . 2.29:

    ().

    ().

    ().

    , , , .

    , ,

    :

    :

    8 (1/8) + 6 (1/2) = 4

    :

    8 (1/8) + 1 (1) = 2

    :

    8 (1/8) + 2 (1/2) = 2

    ,

    . , ,

    . ,

  • 7/25/2019 Crystalography (1)

    46/47

    90

    -Fe Fe, .

    Fe, . Fe.

    , , .

    , ( : CsCl)

    , ,

    [Cs+Cl-] (. 2.30). (:

    NaCl)

    , [Na+Cl-]. ,

    (CaF2) [Ca2+

    2F-].

    , . .

    .

    . 2.30: (CsCl)

    , .. ,

    . .

    ,

    , .. NaCl

    4 [Na+Cl-], 4 Na+4 Cl-(1:1),

    CaF24 Ca2+ 8 F-(1:2). ,

    ,

    .

    , ,

    , , (

    )

    .

  • 7/25/2019 Crystalography (1)

    47/47

    91

    :

    A

    mol1

    D

    =

    =

    =

    Avogadro.

    VZ, : V = (

    ), :

    ANV

    ZD

    =

    V:V = a

    (b

    c).

    , :

    ) ()

    , )

    , )

    (D)

    ( ) /

    ,

    .