tugas fisika zat padat chapter 2

Upload: fahyu

Post on 24-Feb-2018

223 views

Category:

Documents


0 download

TRANSCRIPT

  • 7/24/2019 Tugas Fisika Zat Padat Chapter 2

    1/4

    Nama Kelompok:

    Dewi Hardianti (130322615541)

    Fahyrinda !r"iari#mana (130322615545)

    $mam %antowi (130322615540)

    &i#a 'malia ari (13032261554)*hammad Firman#yah (13032261550+)

    ,ini $#mi -anti (13032261553)

    .hapter 2

    1. The crystal plane with Miller hkl is a plan defined by the points a1/h, a2/k,

    and a3/l.

    a. Two vectors that lie in the plane may be taken as a1/h a2/k and a1/h -

    a3/l. !t each of these vectors "ives #ero as its scalar prod!ct with

    /ha1 ka2 la3, so that /m!s be perpendic!lar to the plane hkl.

    b. $f n is the !nit normal to the plane, the interplanar spacin" is n

    a1h. !tn

    // whence d%hkl& ' (.a1/h)() ' 2*/)()

    c. +or a simple c!bic lattice / %2*/a&%h ^x

    k y

    l ^z

    &, whence

    222

    2

    2

    222

    2

    2

    2 -

    1

    lkh

    ad

    a

    lkhG

    d

    ++=

    ++==

    2.

    ( ) ( ) zcayaxaayaxaa ..2.23.2.23 321

    22

    1

    1 =+

    =+

    =

    a. 0ell vol!me a1.a2a3

    ca

    c

    aa

    aa

    axaa

    2

    321

    32

    1

    2

    13

    2

    1

    2

    13

    2

    1

    =

    =

  • 7/24/2019 Tugas Fisika Zat Padat Chapter 2

    2/4

    b. rimitive translation of the reciprocal lattice

    zc

    aa

    aa

    zyx

    caxaaa

    xaab

    yxa

    c

    aa

    zyx

    caxaaa

    xaab

    yxa

    c

    aa

    zyx

    caxaaa

    xaab

    .2

    2

    13

    2

    1

    2

    13

    2

    1

    ...

    3

    -2

    .2

    1.

    3

    2

    2

    13

    2

    1

    ...

    3

    -2

    ..3

    12

    2

    13

    2

    1

    ...

    3

    -2

    2321

    213

    2321

    312

    2321

    321

    =

    ==

    =

    +=

    ==

    =

    +=

    ==

    =

    c. 4i vectors in the reciprocal lattice are shown as solid lines. The

    broken lines are the pendic!lar bisectors at the midpoints. The

    inscribed hea"on forms the first rillo!in 5one.

    3. y definition of the primitive reciprocal lattice vectors6

    ( )( ) ( ) ( )( )

    ( ) ( )

    ( ) c

    BZ

    V

    xaaaxaaa

    xaaxaaxaaV

    3

    321

    3

    3

    321

    2113323

    2

    /22

    =

    =

    =

    +or the vector identity, see (. 7. 8orn and T. M. 8orn, Mathematical

    handbook for scientists and en"ineers, Mc(raw-9ill, 1:;1, p. 1

  • 7/24/2019 Tugas Fisika Zat Padat Chapter 2

    3/4

    .

    ( )[ ]( )[ ]kai

    kaiMF

    =ep1

    ep1

    x

    xx

    MM

    M

    M

    =

    1

    11

    a. This follows by formin"

    ( )[ ]( )[ ]

    ( )[ ]( )[ ]

    ( )( )

    ( )

    ( )ka

    kaM

    ka

    kaM

    kai

    kaiM

    kai

    kaiMF

    =

    =

    =

    2

    1sin

    2

    1sin

    cos1

    cos1

    ep1

    ep1

    ep1

    ep1

    2

    2

    2

    b. The first #ero in2

    1sin

    M=occ!rs for

    M 2=. That is the correct

    consideration follows from

    MMhMMhhM2

    1sincos

    2

    1cossin

    2

    1sin +=

    +

    >.

    ( ) ( ) ++=j

    vzvyvxi jjjefvvvS 3212

    321

    ?effered to an fcc lattice, thr@e basis of diamond is -

    1

    -

    1

    -

    1

    . Th!s in the

    prod!ct

    ( ) ( ) ( )basisSxlaticefccSvvvS =321,

    Ae take the lattice str!ct!re factor from %=&, and for the basis

    ( ) ( )321

    2

    1

    1vvvi

    ebasisS++

    +=

    now 4%fcc& ' only if all indices are eeven or all indices are odd. $f all

    indices are even str!ct!re factor of the basis vanishes !nless v1 v2

    v3'n, where n is an inte"er. +or eample, for the reflection %222& we have

    ( ) 31 iebasisS +=, and this reflection is forbidden

    5ero as

    Mh isan

    B

  • 7/24/2019 Tugas Fisika Zat Padat Chapter 2

    4/4

    ;.

    ( ) ( )

    ( ) ( )( )( ) ( )

    ( )222

    22

    2

    3

    3

    3

    3

    13

    2

    -1;

    1--

    2epsin-

    2epsin-

    aG

    aGrGaaG

    GaxxxdxaG

    drarGrGrarfG

    +=

    +==

    =

    The inte"ral is not diffic!lt it is "iven as Cwi"ht =;,=1. Dbserve that f'1

    for (' and f E 1/(for (aFF1.