Table S1.  Crystal data and structure refinement for ZnCl4_300K_a.
Identification code 	ZnCl4_300K_a
Empirical formula 	C5 H16 Cl4 N2 Zn
Formula weight 	311.37
Temperature 	300(2) K
Wavelength 	0.71073 Å
Crystal system 	Monoclinic
Space group 	C2/c
Unit cell dimensions	a = 21.4175(12) Å	a= 90°.
	b = 7.3574(3) Å	b= 120.5190(10)°.
	c = 19.1079(16) Å	g = 90°.
Volume	2593.8(3) Å3
Z	8
Density (calculated)	1.595 Mg/m3
Absorption coefficient	2.677 mm-1
F(000)	1264
Crystal size	0.350 x 0.190 x 0.120 mm3
Theta range for data collection	2.208 to 28.320°.
Index ranges	-28<=h<=28, -9<=k<=9, -25<=l<=25
Reflections collected	25987
Independent reflections	3219 [R(int) = 0.0268]
Completeness to theta = 25.242°	99.2 % 
Absorption correction	Semi-empirical from equivalents
Max. and min. transmission	0.7457 and 0.6276
Refinement method	Full-matrix least-squares on F2
Data / restraints / parameters	3219 / 0 / 110
Goodness-of-fit on F2	1.058
Final R indices [I>2sigma(I)]	R1 = 0.0211, wR2 = 0.0513
R indices (all data)	R1 = 0.0248, wR2 = 0.0531
Extinction coefficient	0.0042(2)
Largest diff. peak and hole	0.276 and -0.267 e.Å-3

 Table S2.  Atomic coordinates  ( x 104) and equivalent  isotropic displacement parameters (Å2x 103)
for ZnCl4_300K_a.  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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Zn(1)	3738(1)	2842(1)	3377(1)	40(1)
Cl(1)	3377(1)	3319(1)	4307(1)	45(1)
Cl(2)	2761(1)	3168(1)	2122(1)	54(1)
Cl(3)	4305(1)	128(1)	3593(1)	48(1)
Cl(4)	4581(1)	5023(1)	3608(1)	48(1)
N(1)	1718(1)	2399(2)	2948(1)	50(1)
N(2)	834(1)	7769(2)	5170(1)	50(1)
C(1)	1361(1)	2041(3)	3430(1)	57(1)
C(2)	1066(1)	3756(3)	3586(1)	55(1)
C(3)	1638(1)	5168(2)	4080(1)	54(1)
C(4)	1344(1)	6792(2)	4322(1)	55(1)
C(5)	1192(1)	6284(2)	4985(1)	45(1)
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 Table S3.   Bond lengths [Å] and angles [°] for  ZnCl4_300K_a.
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Zn(1)-Cl(2) 	2.2556(4)
Zn(1)-Cl(3) 	2.2632(4)
Zn(1)-Cl(4) 	2.2841(4)
Zn(1)-Cl(1) 	2.2970(4)
N(1)-C(1) 	1.490(2)
N(1)-H(1NA) 	0.8900
N(1)-H(1NB) 	0.8900
N(1)-H(1NC) 	0.8900
N(2)-C(5) 	1.476(2)
N(2)-H(2NA) 	0.8900
N(2)-H(2NB) 	0.8900
N(2)-H(2NC) 	0.8900
C(1)-C(2) 	1.506(3)
C(1)-H(1A) 	0.9700
C(1)-H(1AB) 	0.9700
C(2)-C(3) 	1.515(3)
C(2)-H(2A) 	0.9700
C(2)-H(2AB) 	0.9700
C(3)-C(4) 	1.527(2)
C(3)-H(3A) 	0.9700
C(3)-H(3AB) 	0.9700
C(4)-C(5) 	1.506(2)
C(4)-H(4A) 	0.9700
C(4)-H(4AB) 	0.9700
C(5)-H(5A) 	0.9700
C(5)-H(5AB) 	0.9700

Cl(2)-Zn(1)-Cl(3)	114.228(18)
Cl(2)-Zn(1)-Cl(4)	110.246(18)
Cl(3)-Zn(1)-Cl(4)	106.651(16)
Cl(2)-Zn(1)-Cl(1)	108.102(18)
Cl(3)-Zn(1)-Cl(1)	110.719(16)
Cl(4)-Zn(1)-Cl(1)	106.641(16)
C(1)-N(1)-H(1NA)	109.5
C(1)-N(1)-H(1NB)	109.5
H(1NA)-N(1)-H(1NB)	109.5
C(1)-N(1)-H(1NC)	109.5
H(1NA)-N(1)-H(1NC)	109.5
H(1NB)-N(1)-H(1NC)	109.5
C(5)-N(2)-H(2NA)	109.5
C(5)-N(2)-H(2NB)	109.5
H(2NA)-N(2)-H(2NB)	109.5
C(5)-N(2)-H(2NC)	109.5
H(2NA)-N(2)-H(2NC)	109.5
H(2NB)-N(2)-H(2NC)	109.5
N(1)-C(1)-C(2)	111.87(15)
N(1)-C(1)-H(1A)	109.2
C(2)-C(1)-H(1A)	109.2
N(1)-C(1)-H(1AB)	109.2
C(2)-C(1)-H(1AB)	109.2
H(1A)-C(1)-H(1AB)	107.9
C(1)-C(2)-C(3)	114.24(15)
C(1)-C(2)-H(2A)	108.7
C(3)-C(2)-H(2A)	108.7
C(1)-C(2)-H(2AB)	108.7
C(3)-C(2)-H(2AB)	108.7
H(2A)-C(2)-H(2AB)	107.6
C(2)-C(3)-C(4)	113.52(15)
C(2)-C(3)-H(3A)	108.9
C(4)-C(3)-H(3A)	108.9
C(2)-C(3)-H(3AB)	108.9
C(4)-C(3)-H(3AB)	108.9
H(3A)-C(3)-H(3AB)	107.7
C(5)-C(4)-C(3)	111.03(14)
C(5)-C(4)-H(4A)	109.4
C(3)-C(4)-H(4A)	109.4
C(5)-C(4)-H(4AB)	109.4
C(3)-C(4)-H(4AB)	109.4
H(4A)-C(4)-H(4AB)	108.0
N(2)-C(5)-C(4)	112.21(14)
N(2)-C(5)-H(5A)	109.2
C(4)-C(5)-H(5A)	109.2
N(2)-C(5)-H(5AB)	109.2
C(4)-C(5)-H(5AB)	109.2
H(5A)-C(5)-H(5AB)	107.9
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Symmetry transformations used to generate equivalent atoms: 

 Table S4.   Anisotropic displacement parameters  (Å2x 103) for ZnCl4_300K_a.  The anisotropic
displacement factor exponent takes the form:  -2p2[ h2 a*2U11 + ...  + 2 h k a* b* U12 ]
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	U11	U22 	U33	U23	U13	U12
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Zn(1)	42(1) 	35(1)	40(1) 	1(1)	20(1) 	3(1)
Cl(1)	51(1) 	44(1)	43(1) 	-2(1)	26(1) 	2(1)
Cl(2)	50(1) 	64(1)	39(1) 	2(1)	16(1) 	0(1)
Cl(3)	52(1) 	35(1)	59(1) 	3(1)	30(1) 	7(1)
Cl(4)	49(1) 	38(1)	55(1) 	5(1)	26(1) 	-1(1)
N(1)	49(1) 	59(1)	44(1) 	-13(1)	24(1) 	0(1)
N(2)	64(1) 	41(1)	50(1) 	-2(1)	33(1) 	4(1)
C(1)	72(1) 	55(1)	54(1) 	-13(1)	39(1) 	-12(1)
C(2)	51(1) 	71(1)	50(1) 	-11(1)	32(1) 	-2(1)
C(3)	60(1) 	49(1)	70(1) 	-6(1)	45(1) 	-2(1)
C(4)	70(1) 	40(1)	74(1) 	1(1)	51(1) 	1(1)
C(5)	53(1) 	39(1)	40(1) 	0(1)	22(1) 	8(1)
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 Table S5.   Hydrogen coordinates ( x 104) and isotropic  displacement parameters (Å2x 10 3)
for ZnCl4_300K_a.
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	x 	y 	z 	U(eq)
________________________________________________________________________________ 
 
H(1NA)	1886	1360	2868	75
H(1NB)	1398	2881	2471	75
H(1NC)	2085	3169	3218	75
H(2NA)	754	7417	5563	75
H(2NB)	1119	8745	5332	75
H(2NC)	415	8039	4726	75
H(1A)	1709	1495	3945	68
H(1AB)	968	1183	3139	68
H(2A)	812	3442	3869	66
H(2AB)	716	4287	3068	66
H(3A)	1849	5601	3766	65
H(3AB)	2020	4598	4568	65
H(4A)	1695	7773	4510	66
H(4AB)	902	7222	3852	66
H(5A)	884	5216	4819	54
H(5AB)	1644	5977	5472	54
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