Plana density

O o

S

CO Ə

to There

A=

الدا

Ⓒ

3

ex

b

9

ooo

B

19 10

bord

of b

3

atoms

2D repeat

Planow density

BE

unit

as

2 ah

EX

area

2D repeat unit

20

D

T

R

2

6

a

-

(111) Все ре

F

15

1 atom in plane / unit surface

3

3

√29

I

16√3

3

*

@A

ra

2

a

O

XXX A

(1

9

2

R

31

@

x A

O

Q

1

A above plane

x under plane

cell

4√3

3

17

-R

7 atoms

2

OM

2