, . . , , .

. 23.

23. , ( Ǻ)

α

18,2418,31

18,200,05

18,2518,30

18,2518,30

8,93

8,910,01

8,838,88

8,838,88

5,185,20

5,170,05

6,195,20

5,195,20

, 1960

Harris, 1968

Meyer, 1968

. . . . - (1964) - : (011) [111] (010) [100] .

, ; , , .

. - . . . (Williams, 1932) .