Table 1.  Crystal data and structure refinement for twin4a.
Identification code 	shelx
Empirical formula 	C15 H24 Cl Ir N2
Formula weight 	460.01
Temperature 	100(2) K
Wavelength 	0.71073 Å
Crystal system 	Orthorhombic
Space group 	C m c a
Unit cell dimensions	a = 8.956(2) Å	a= 90°.
	b = 14.380(2) Å	b= 90°.
	c = 24.831(5) Å	g = 90°.
Volume	3197.8(11) Å3
Z	8
Density (calculated)	1.911 Mg/m3
Absorption coefficient	8.507 mm-1
F(000)	1776
Crystal size	0.400 x 0.070 x 0.060 mm3
Theta range for data collection	1.640 to 25.147°.
Index ranges	-10<=h<=10, -17<=k<=17, -29<=l<=0
Reflections collected	5449
Independent reflections	1516 [R(int) = 0.1183]
Completeness to theta = 25.000°	98.6 % 
Refinement method	Full-matrix least-squares on F2
Data / restraints / parameters	1516 / 135 / 187
Goodness-of-fit on F2	1.162
Final R indices [I>2sigma(I)]	R1 = 0.0324, wR2 = 0.0669
R indices (all data)	R1 = 0.0393, wR2 = 0.0696
Extinction coefficient	n/a
Largest diff. peak and hole	1.231 and -2.170 e.Å-3

Table 2.  Atomic coordinates ( x 104) and equivalent isotropic displacement parameters (Å2x 103)
for twin4a.  U(eq) is defined as one third of the trace of the orthogonalized Uij tensor.
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	x	y	z	U(eq)
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C(7)	424(11)	3778(6)	5513(5)	33(4)
C(6)	-435(10)	1926(8)	4880(4)	41(4)
C(3)	964(11)	2846(6)	5641(4)	22(3)
C(2)	634(11)	2004(7)	5352(4)	22(2)
C(1)	1455(8)	1274(9)	5583(3)	25(3)
C(5)	2399(15)	1642(8)	5981(6)	8(4)
C(4)	2059(10)	2613(6)	6047(4)	19(2)
C(9)	3507(11)	1098(8)	6320(4)	30(3)
C(8)	2801(13)	3266(7)	6408(5)	37(3)
C(14)	1358(10)	1298(8)	7486(4)	28(3)
C(11)	-50(30)	-202(6)	7435(3)	25(2)
N(1)	351(8)	640(6)	7220(3)	22(3)
C(10)	-251(13)	750(7)	6719(3)	23(3)
N(2)	-1000(9)	-68(5)	6643(3)	22(2)
C(12)	-832(12)	-640(6)	7081(4)	30(3)
C(13)	-1805(14)	-331(9)	6152(4)	37(3)
Cl(1)	-1044(7)	2808(6)	6878(3)	24(2)
C(15)	-2090(40)	1640(30)	6014(15)	23(6)
Cl(1B)	-2634(9)	1971(5)	6063(3)	21(2)
C(15B)	-530(30)	2730(30)	6860(15)	27(6)
Ir(1)	0	1825(1)	6209(1)	17(1)
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Table 3.   Bond lengths [Å] and angles [°] for twin4a.
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C(7)-C(3) 	1.459(11)
C(7)-H(7A) 	0.9600
C(7)-H(7B) 	0.9600
C(7)-H(7C) 	0.9600
C(6)-C(2) 	1.518(12)
C(6)-H(6A) 	0.9367
C(6)-H(6B) 	0.9600
C(6)-H(6C) 	0.9600
C(3)-C(2) 	1.437(12)
C(3)-C(4) 	1.446(15)
C(3)-Ir(1) 	2.213(10)
C(2)-C(1) 	1.403(13)
C(2)-Ir(1) 	2.218(10)
C(1)-C(5) 	1.404(13)
C(1)-Ir(1) 	2.177(10)
C(1)-H(1) 	0.9300
C(5)-C(4) 	1.438(12)
C(5)-C(9) 	1.518(12)
C(5)-Ir(1) 	2.238(15)
C(4)-C(8) 	1.459(11)
C(4)-Ir(1) 	2.202(9)
C(9)-H(9A) 	0.9600
C(9)-H(9B) 	0.9600
C(9)-H(9C) 	0.9600
C(8)-H(8A) 	0.9600
C(8)-H(8B) 	0.9600
C(8)-H(8C) 	0.9600
C(14)-N(1) 	1.464(10)
C(14)-H(14A) 	0.9600
C(14)-H(14B) 	0.9600
C(14)-H(14C) 	0.9600
C(11)-C(12) 	1.29(2)
C(11)-N(1) 	1.371(10)
C(11)-H(11) 	0.9299
N(1)-C(10) 	1.367(9)
C(10)-N(2) 	1.367(9)
C(10)-Ir(1) 	2.010(10)
N(2)-C(12) 	1.371(10)
N(2)-C(13) 	1.464(10)
C(12)-H(12) 	0.9300
C(13)-H(13A) 	0.9600
C(13)-H(13B) 	0.9600
C(13)-H(13C) 	0.9601
Cl(1)-Ir(1) 	2.372(7)
C(15)-Ir(1) 	1.95(3)
C(15)-H(15A) 	0.9600
C(15)-H(15B) 	0.9600
C(15)-H(15C) 	0.9600
Cl(1B)-Ir(1) 	2.396(8)
C(15B)-Ir(1) 	2.13(3)
C(15B)-H(15D) 	0.9599
C(15B)-H(15E) 	0.9600
C(15B)-H(15F) 	0.9600

C(3)-C(7)-H(7A)	109.1
C(3)-C(7)-H(7B)	109.3
H(7A)-C(7)-H(7B)	109.5
C(3)-C(7)-H(7C)	110.0
H(7A)-C(7)-H(7C)	109.5
H(7B)-C(7)-H(7C)	109.5
C(2)-C(6)-H(6A)	111.7
C(2)-C(6)-H(6B)	108.8
H(6A)-C(6)-H(6B)	107.3
C(2)-C(6)-H(6C)	110.6
H(6A)-C(6)-H(6C)	108.9
H(6B)-C(6)-H(6C)	109.5
C(2)-C(3)-C(4)	106.9(5)
C(2)-C(3)-C(7)	126.7(7)
C(4)-C(3)-C(7)	126.1(5)
C(2)-C(3)-Ir(1)	71.3(5)
C(4)-C(3)-Ir(1)	70.5(5)
C(7)-C(3)-Ir(1)	128.2(7)
C(1)-C(2)-C(3)	108.6(8)
C(1)-C(2)-C(6)	126.2(9)
C(3)-C(2)-C(6)	125.2(9)
C(1)-C(2)-Ir(1)	69.8(6)
C(3)-C(2)-Ir(1)	70.9(5)
C(6)-C(2)-Ir(1)	124.8(7)
C(2)-C(1)-C(5)	108.7(11)
C(2)-C(1)-Ir(1)	72.9(6)
C(5)-C(1)-Ir(1)	73.8(8)
C(2)-C(1)-H(1)	125.4
C(5)-C(1)-H(1)	125.8
Ir(1)-C(1)-H(1)	121.7
C(1)-C(5)-C(4)	108.5(8)
C(1)-C(5)-C(9)	126.1(9)
C(4)-C(5)-C(9)	125.2(9)
C(1)-C(5)-Ir(1)	69.1(7)
C(4)-C(5)-Ir(1)	69.8(6)
C(9)-C(5)-Ir(1)	123.2(10)
C(5)-C(4)-C(3)	106.8(5)
C(5)-C(4)-C(8)	126.7(7)
C(3)-C(4)-C(8)	126.1(5)
C(5)-C(4)-Ir(1)	72.5(7)
C(3)-C(4)-Ir(1)	71.3(5)
C(8)-C(4)-Ir(1)	126.8(8)
C(5)-C(9)-H(9A)	111.6
C(5)-C(9)-H(9B)	112.2
H(9A)-C(9)-H(9B)	109.5
C(5)-C(9)-H(9C)	104.4
H(9A)-C(9)-H(9C)	109.5
H(9B)-C(9)-H(9C)	109.5
C(4)-C(8)-H(8A)	111.2
C(4)-C(8)-H(8B)	108.3
H(8A)-C(8)-H(8B)	109.5
C(4)-C(8)-H(8C)	108.9
H(8A)-C(8)-H(8C)	109.5
H(8B)-C(8)-H(8C)	109.5
N(1)-C(14)-H(14A)	109.0
N(1)-C(14)-H(14B)	109.4
H(14A)-C(14)-H(14B)	109.5
N(1)-C(14)-H(14C)	110.1
H(14A)-C(14)-H(14C)	109.5
H(14B)-C(14)-H(14C)	109.5
C(12)-C(11)-N(1)	108.0(5)
C(12)-C(11)-H(11)	127.0
N(1)-C(11)-H(11)	124.9
C(10)-N(1)-C(11)	110.6(7)
C(10)-N(1)-C(14)	125.3(7)
C(11)-N(1)-C(14)	124.0(7)
N(1)-C(10)-N(2)	102.7(9)
N(1)-C(10)-Ir(1)	128.2(5)
N(2)-C(10)-Ir(1)	129.1(5)
C(10)-N(2)-C(12)	110.7(7)
C(10)-N(2)-C(13)	125.3(7)
C(12)-N(2)-C(13)	124.0(7)
C(11)-C(12)-N(2)	108.0(5)
C(11)-C(12)-H(12)	126.4
N(2)-C(12)-H(12)	125.6
N(2)-C(13)-H(13A)	109.0
N(2)-C(13)-H(13B)	110.0
H(13A)-C(13)-H(13B)	109.5
N(2)-C(13)-H(13C)	109.4
H(13A)-C(13)-H(13C)	109.5
H(13B)-C(13)-H(13C)	109.5
Ir(1)-C(15)-H(15A)	111.2
Ir(1)-C(15)-H(15B)	109.9
H(15A)-C(15)-H(15B)	109.5
Ir(1)-C(15)-H(15C)	107.3
H(15A)-C(15)-H(15C)	109.5
H(15B)-C(15)-H(15C)	109.5
Ir(1)-C(15B)-H(15D)	109.8
Ir(1)-C(15B)-H(15E)	110.7
H(15D)-C(15B)-H(15E)	109.5
Ir(1)-C(15B)-H(15F)	107.9
H(15D)-C(15B)-H(15F)	109.5
H(15E)-C(15B)-H(15F)	109.5
C(15)-Ir(1)-C(10)	86.7(12)
C(15)-Ir(1)-C(1)	110.2(10)
C(10)-Ir(1)-C(1)	103.7(5)
C(15)-Ir(1)-C(4)	146.0(12)
C(10)-Ir(1)-C(4)	127.2(4)
C(1)-Ir(1)-C(4)	63.6(4)
C(15)-Ir(1)-C(3)	107.9(12)
C(10)-Ir(1)-C(3)	162.9(4)
C(1)-Ir(1)-C(3)	63.4(4)
C(4)-Ir(1)-C(3)	38.2(4)
C(15)-Ir(1)-C(2)	91.3(12)
C(10)-Ir(1)-C(2)	136.2(4)
C(1)-Ir(1)-C(2)	37.2(3)
C(4)-Ir(1)-C(2)	63.2(3)
C(3)-Ir(1)-C(2)	37.9(3)
C(15)-Ir(1)-C(5)	147.3(9)
C(10)-Ir(1)-C(5)	100.2(5)
C(1)-Ir(1)-C(5)	37.0(3)
C(4)-Ir(1)-C(5)	37.8(3)
C(3)-Ir(1)-C(5)	62.7(4)
C(2)-Ir(1)-C(5)	61.6(5)
C(15)-Ir(1)-Cl(1)	83.0(9)
C(10)-Ir(1)-Cl(1)	88.5(4)
C(1)-Ir(1)-Cl(1)	162.2(4)
C(4)-Ir(1)-Cl(1)	98.7(3)
C(3)-Ir(1)-Cl(1)	101.8(3)
C(2)-Ir(1)-Cl(1)	134.7(3)
C(5)-Ir(1)-Cl(1)	128.7(3)
C(15B)-Ir(1)-Cl(1B)	80.9(7)
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Symmetry transformations used to generate equivalent atoms: 

Table 4.   Anisotropic displacement parameters (Å2x 103)for twin4a.  The anisotropic
displacement factor exponent takes the form: -2p2[ h2a*2U11 + ... + 2 h k a* b* U12 ]
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	U11	U22	U33	U23	U13	U12
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C(7)	30(9) 	29(6)	40(6) 	17(6)	8(4) 	1(5)
C(6)	37(8) 	63(9)	24(5) 	4(6)	1(4) 	2(6)
C(3)	18(5) 	22(5)	26(5) 	8(4)	7(4) 	-4(4)
C(2)	19(4) 	28(5)	18(4) 	-2(4)	4(3) 	-6(4)
C(1)	21(5) 	28(5)	24(5) 	1(5)	5(4) 	-5(4)
C(5)	3(6) 	7(6)	13(6) 	-1(5)	4(5) 	0(5)
C(4)	17(4) 	18(5)	21(4) 	5(4)	3(4) 	-3(4)
C(9)	20(6) 	36(7)	33(6) 	5(6)	3(5) 	3(5)
C(8)	35(6) 	35(7)	41(6) 	2(7)	-1(6) 	-5(6)
C(14)	23(6) 	41(7)	21(5) 	-3(6)	-2(4) 	0(5)
C(11)	27(4) 	21(4)	26(4) 	10(3)	1(7) 	1(7)
N(1)	19(6) 	27(4)	19(3) 	4(3)	1(3) 	1(3)
C(10)	20(7) 	16(4)	32(4) 	-4(4)	-9(4) 	-6(4)
N(2)	20(4) 	21(4)	26(4) 	5(4)	3(3) 	-5(4)
C(12)	32(5) 	22(5)	35(5) 	4(5)	11(4) 	4(4)
C(13)	39(7) 	36(8)	35(6) 	-17(6)	1(5) 	-18(6)
Cl(1)	27(4) 	15(3)	30(3) 	-8(3)	5(3) 	2(3)
C(15)	24(9) 	21(9)	23(8) 	1(8)	8(8) 	11(7)
Cl(1B)	16(4) 	25(5)	22(3) 	-8(3)	-2(3) 	6(3)
C(15B)	28(10) 	20(8)	32(8) 	-1(7)	2(8) 	12(8)
Ir(1)	19(1) 	16(1)	16(1) 	3(1)	0 	0
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Table 5.   Hydrogen coordinates ( x 104) and isotropic displacement parameters (Å2x 103)
for twin4a.
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	x 	y 	z 	U(eq)
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H(7A)	-176	3750	5193	50
H(7B)	1261	4182	5452	50
H(7C)	-165	4014	5805	50
H(6A)	5	2129	4559	62
H(6B)	-1282	2319	4947	62
H(6C)	-764	1295	4835	62
H(1)	1413	655	5477	30
H(9A)	3297	444	6314	45
H(9B)	3538	1312	6686	45
H(9C)	4455	1211	6151	45
H(8A)	3372	2945	6678	55
H(8B)	2050	3639	6580	55
H(8C)	3450	3658	6201	55
H(14A)	1481	1833	7259	42
H(14B)	2310	1008	7543	42
H(14C)	948	1488	7826	42
H(11)	240	-420	7771	30
H(12)	-1240	-1231	7117	36
H(13A)	-2857	-258	6213	55
H(13B)	-1594	-967	6062	55
H(13C)	-1499	65	5861	55
H(15A)	-2451	1052	6147	34
H(15B)	-2196	1657	5630	34
H(15C)	-2650	2134	6173	34
H(15D)	-711	2377	7180	40
H(15E)	-1401	3097	6777	40
H(15F)	306	3138	6916	40
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