Table 2. Selected geometric parameters (, ) for (2) .

Si1N1	1.809(3)	Si2C13	1.839(6)
Si1C11	1.842(5)	Si2C15	1.854(6)
Si1C12	1.842(5)	Si2C14	1.861(5)
Si1C10	1.847(5)	S1C2	1.669(4)
Si2N3	1.803(3)
N1Si1C11	109.0(2)	N3Si2C14	109.3(2)
N1Si1C12	109.53(19)	C13Si2C14	113.7(3)
C11Si1C12	113.9(3)	C15Si2C14	107.7(3)
N1Si1C10	108.4(2)	C2N1Si1	121.7(3)
C11Si1C10	109.4(3)	C8N1Si1	130.9(3)
C12Si1C10	106.4(3)	C2N3Si2	120.8(3)
N3Si2C13	109.4(2)	C9N3Si2	132.3(2)
N3Si2C15	108.5(2)	N1C2S1	125.1(3)
C13Si2C15	108.2(3)	N3C2S1	124.8(3)
C11Si1N1C2	70.3(4)	C14Si2N3C9	113.9(4)
C12Si1N1C2	55.0(4)	Si2N3C9C4	4.8(7)
C10Si1N1C2	170.7(3)	Si2N3C9C8	179.1(3)
C11Si1N1C8	113.2(4)	Si1N1C8C7	10.2(6)
C12Si1N1C8	121.5(4)	Si1N1C8C9	174.1(3)
C10Si1N1C8	5.8(4)	Si1N1C2N3	173.6(2)
C13Si2N3C2	59.4(4)	C8N1C2S1	175.3(3)
C15Si2N3C2	177.2(4)	Si1N1C2S1	7.5(5)
C14Si2N3C2	65.7(4)	Si2N3C2N1	177.2(2)
C13Si2N3C9	121.0(4)	C9N3C2S1	175.9(3)
C15Si2N3C9	3.2(4)	Si2N3C2S1	3.9(5)