Di-μ-azido-κ⁴N:N-bis­[(azido-κN)(2,9-dimethyl-1,10-phenanthroline-κ²N,N′)nickel(II)]

The title complex, [Ni₂(N₃)₄(C₁₄H₁₂N₂)₂], is a centrosymmetric dimer in which each Ni^II atom is coordinated by five N atoms (two from a 2,9-dimethyl-1,10-phenanthroline ligand, two from the bridging azide group and one from the terminal azide) in a slightly distorted square-pyramidal geometry. The Ni...Ni distance is 3.2532 (9) Å. In the crystal structure, mol­ecules are linked into one-dimensional chains by C—H...N hydrogen bonds and π–π stacking inter­actions [π-π interaction distance = 3.6215 (16) Å].

Key indicators

• Single-crystal X-ray study
• T = 153 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.033
• wR factor = 0.083
• Data-to-parameter ratio = 16.2

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT230_ALERT_2_C Hirshfeld Test Diff for    N3     -   N4      ..       6.62 su
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         N7
PLAT380_ALERT_4_C Check Incorrectly? Oriented X(sp2)-Methyl Moiety        C14

Alert level G
PLAT794_ALERT_5_G Check Predicted Bond Valency for Ni1         (2)       1.97

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   3 ALERT level C = Check and explain
   1 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

The azide ion is a versatile ligand, it can bind metal ions in a number of coordination modes, giving rise to mononuclear, dinuclear and polynuclear complexes. In these complexes different types of bonding of the azido ligands have been observed; either simple monodentate terminal fashion or bridging end-to-end (1,3-di-µ) or end-on (1,1-di-µ) modes (Grove et al., 2001; Zhao et al., 2003; Wang et al., 2004; Li et al., 2005; You, 2005; Qian et al., 2007; Cai et al., 2007).

The title compound is centrosymmetric. In this complex, the two nickel(II) atoms are doubly bridged by two end-on azido groups (Fig 1). Each nickel atom is located in a slightly distored square-pyramidal geometry, being surrounded by five nitrogen atoms (two of a 2,9-dimethyl-1,10-phenanthroline, two of the bridging azido group and the last one of the terminal azide). A N atom of the 2,9-dimethyl-1,10-phenanthroline is located in the axial position and the ligand bond lengths and angles fall in the ranges of 1.985 (2)–2.070 (2) Å and 76.09 (9)–160.44 (9)°, respectively. The Ni···Ni distance is 3.2532 (9) Å.

π–π interactions between the phenanthroline rings (Fig. 2) is observed with a Cg(6)-Cg(6)ⁱ (ring Cg(6): C5, C6, C7, C8, C12, C13; symmetry code: (i) -x, y, 1/2 - z) distance of 3.6215 (16) Å. These π-π stacking interactions and C—H···N hydrogen bonds lead to one dimensional chains.

Related literature

For related literature, see: Cai et al. (2007); Grove et al. (2001); Li et al. (2005); Qian et al. (2007); Wang et al. (2004); You (2005); Zhao et al. (2003).

S2. Experimental

The title compound was sythesized as follows: To a methanolic solution (10 ml) of nickel(II) perchlorate hexahydrate (0.183 g, 0.5 mmol), 2,9-dimethyl-1,10-phenanthroline (0.104 g, 0.5 mmol) and sodium azide (0.046 g, 0.7 mmol) were added with stirring. The resulting green solution was stirred for 0.5 h at room temperature. Slow evaporation of the solution yielded a green crystalline compound.

S3. Refinement

The hydrogen atoms were assigned with isotropic displacement factors and included in the final refinement cycles by use of geometrical restraints (C_ar–H = 0.93 Å; C_Me–H = 0.96 Å).

Computing details

Data collection: COLLECT (Nonius, 1998); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO (Otwinowski & Minor, 1997) and maXus (Mackay et al., 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1997); software used to prepare material for publication: SHELXL97.

Figures

	Fig. 1. The title compound, showing 30% probability displacement ellipsoids (Symmetry codes: -x + 3/2, -y + 3/2, -z + 2). Hydrogen atoms are omitted for clarity.
	Fig. 2. The intermolecular π-π stacking and C—H···N interactions.

Di-µ-azido-κ⁴N:N-bis[(azido-κN)(2,9-dimethyl-1,10-phenanthroline- κN,N)nickel(II)]

Crystal data

[Ni2(N3)4(C14H12N2)2]	F(000) = 1440
Mr = 702.01	Dx = 1.577 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 13380 reflections
a = 13.471 (3) Å	θ = 3.4–27.5°
b = 11.226 (2) Å	µ = 1.33 mm^−1
c = 19.605 (4) Å	T = 153 K
β = 94.36 (3)°	Block, green
V = 2956.2 (10) Å^3	0.10 × 0.10 × 0.05 mm
Z = 4

Data collection

Nonius KappaCCD diffractometer	3396 independent reflections
Radiation source: fine-focus sealed tube	1923 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.032
Detector resolution: 18 pixels mm^-1	θmax = 27.5°, θmin = 3.6°
ω scans	h = −17→17
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	k = −14→14
Tmin = 0.879, Tmax = 0.937	l = −25→25
6614 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.033	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.083	H-atom parameters constrained
S = 0.93	w = 1/[σ^2(Fo^2) + (0.0402P)^2] where P = (Fo^2 + 2Fc^2)/3
3396 reflections	(Δ/σ)max = 0.002
210 parameters	Δρmax = 0.31 e Å^−3
0 restraints	Δρmin = −0.41 e Å^−3

Special details

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > 2σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Ni1	0.84958 (2)	0.75286 (3)	0.958017 (13)	0.03719 (11)
N1	0.86582 (14)	0.8208 (2)	0.86198 (10)	0.0385 (5)
C12	0.86702 (16)	0.6124 (2)	0.83785 (12)	0.0385 (6)
N2	0.86412 (14)	0.59478 (19)	0.90696 (10)	0.0387 (5)
C13	0.86592 (17)	0.7327 (2)	0.81366 (12)	0.0378 (6)
N3	0.69573 (14)	0.7560 (2)	0.94405 (9)	0.0436 (5)
N4	0.64685 (16)	0.7357 (2)	0.89104 (11)	0.0483 (6)
C7	0.8734 (2)	0.5456 (3)	0.71970 (13)	0.0568 (8)
H7	0.8757	0.4837	0.6884	0.068*
N7	1.05529 (18)	0.8271 (2)	0.96773 (10)	0.0521 (6)
C3	0.8736 (2)	0.9632 (3)	0.77282 (14)	0.0535 (8)
H3	0.8767	1.0427	0.7600	0.064*
C2	0.87088 (18)	0.9336 (2)	0.84214 (13)	0.0430 (6)
C5	0.86905 (18)	0.7572 (3)	0.74372 (12)	0.0447 (6)
C9	0.8781 (2)	0.4033 (3)	0.81853 (15)	0.0578 (8)
H9	0.8826	0.3379	0.7898	0.069*
N6	0.98706 (17)	0.7894 (2)	0.99584 (11)	0.0542 (6)
C4	0.8717 (2)	0.8767 (3)	0.72427 (13)	0.0526 (7)
H4	0.8721	0.8971	0.6783	0.063*
C8	0.87256 (19)	0.5188 (3)	0.79084 (14)	0.0480 (7)
C11	0.86797 (19)	0.4847 (2)	0.93092 (13)	0.0441 (6)
C14	0.8643 (2)	0.4653 (3)	1.00651 (13)	0.0579 (8)
H14A	0.8584	0.5408	1.0289	0.087*
H14B	0.9243	0.4263	1.0242	0.087*
H14C	0.8079	0.4165	1.0147	0.087*
C10	0.8768 (2)	0.3867 (3)	0.88718 (15)	0.0574 (8)
H10	0.8818	0.3101	0.9053	0.069*
C6	0.8709 (2)	0.6584 (3)	0.69726 (13)	0.0554 (8)
H6	0.8703	0.6731	0.6505	0.066*
C1	0.8750 (2)	1.0281 (2)	0.89582 (14)	0.0564 (8)
H1A	0.8671	0.9925	0.9396	0.085*
H1B	0.8225	1.0846	0.8855	0.085*
H1C	0.9381	1.0681	0.8969	0.085*
N5	0.6021 (2)	0.7173 (3)	0.84052 (13)	0.0829 (10)
N8	1.1259 (2)	0.8620 (3)	0.94390 (13)	0.0916 (11)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Ni1	0.03987 (17)	0.04148 (19)	0.03020 (15)	0.00079 (17)	0.00262 (12)	−0.00298 (16)
N1	0.0378 (12)	0.0427 (14)	0.0352 (11)	−0.0019 (10)	0.0031 (9)	−0.0022 (10)
C12	0.0307 (13)	0.0469 (16)	0.0379 (13)	0.0008 (12)	0.0026 (11)	−0.0072 (12)
N2	0.0375 (11)	0.0405 (13)	0.0378 (11)	0.0007 (9)	0.0016 (9)	−0.0017 (10)
C13	0.0315 (11)	0.0489 (18)	0.0331 (11)	−0.0004 (12)	0.0036 (10)	−0.0063 (11)
N3	0.0400 (11)	0.0604 (14)	0.0301 (10)	0.0029 (12)	0.0007 (8)	−0.0045 (11)
N4	0.0450 (12)	0.0616 (16)	0.0387 (12)	0.0033 (12)	0.0056 (10)	−0.0013 (12)
C7	0.0546 (18)	0.074 (2)	0.0422 (17)	−0.0017 (17)	0.0045 (13)	−0.0214 (15)
N7	0.0510 (14)	0.0706 (17)	0.0339 (11)	−0.0038 (13)	−0.0015 (10)	−0.0121 (11)
C3	0.0541 (18)	0.054 (2)	0.0530 (18)	−0.0014 (14)	0.0056 (14)	0.0106 (14)
C2	0.0415 (15)	0.0453 (17)	0.0422 (15)	−0.0016 (12)	0.0021 (12)	0.0022 (12)
C5	0.0364 (12)	0.0635 (17)	0.0340 (12)	−0.0007 (15)	0.0022 (10)	−0.0026 (15)
C9	0.0597 (18)	0.051 (2)	0.0619 (19)	0.0039 (15)	−0.0001 (15)	−0.0226 (15)
N6	0.0458 (13)	0.0739 (17)	0.0424 (12)	−0.0062 (12)	−0.0006 (10)	0.0011 (11)
C4	0.0489 (17)	0.073 (2)	0.0363 (14)	0.0010 (16)	0.0068 (12)	0.0094 (14)
C8	0.0405 (16)	0.0505 (19)	0.0529 (16)	−0.0006 (13)	0.0031 (13)	−0.0147 (14)
C11	0.0421 (15)	0.0406 (16)	0.0490 (15)	0.0017 (12)	0.0008 (12)	−0.0010 (13)
C14	0.070 (2)	0.0483 (18)	0.0554 (17)	0.0037 (15)	0.0061 (15)	0.0074 (14)
C10	0.067 (2)	0.0369 (17)	0.0672 (19)	0.0041 (14)	−0.0007 (16)	−0.0053 (14)
C6	0.0545 (18)	0.078 (2)	0.0335 (14)	−0.0002 (16)	0.0052 (13)	−0.0108 (15)
C1	0.073 (2)	0.0430 (19)	0.0530 (17)	−0.0016 (15)	0.0015 (15)	−0.0015 (14)
N5	0.078 (2)	0.123 (3)	0.0460 (15)	−0.0035 (17)	−0.0102 (13)	−0.0129 (16)
N8	0.077 (2)	0.145 (3)	0.0561 (16)	−0.042 (2)	0.0206 (15)	−0.0117 (18)

Geometric parameters (Å, º)

Ni1—N6	1.985 (2)	C3—C4	1.358 (4)
Ni1—N2	2.054 (2)	C3—C2	1.402 (3)
Ni1—N1	2.058 (2)	C3—H3	0.9300
Ni1—N3^i	2.0607 (19)	C2—C1	1.492 (4)
Ni1—N3	2.070 (2)	C5—C4	1.396 (4)
N1—C2	1.329 (3)	C5—C6	1.436 (4)
N1—C13	1.369 (3)	C9—C10	1.360 (4)
C12—N2	1.373 (3)	C9—C8	1.405 (4)
C12—C8	1.404 (3)	C9—H9	0.9300
C12—C13	1.431 (4)	C4—H4	0.9300
N2—C11	1.322 (3)	C11—C10	1.405 (4)
C13—C5	1.402 (3)	C11—C14	1.502 (3)
N3—N4	1.209 (3)	C14—H14A	0.9600
N3—Ni1^i	2.0607 (19)	C14—H14B	0.9600
N4—N5	1.138 (3)	C14—H14C	0.9600
C7—C6	1.340 (4)	C10—H10	0.9300
C7—C8	1.428 (4)	C6—H6	0.9300
C7—H7	0.9300	C1—H1A	0.9600
N7—N8	1.159 (3)	C1—H1B	0.9600
N7—N6	1.185 (3)	C1—H1C	0.9600
N6—Ni1—N2	103.88 (9)	C3—C2—C1	120.9 (3)
N6—Ni1—N1	95.98 (9)	C4—C5—C13	117.3 (2)
N2—Ni1—N1	81.58 (8)	C4—C5—C6	124.5 (2)
N6—Ni1—N3^i	89.76 (9)	C13—C5—C6	118.2 (3)
N2—Ni1—N3^i	117.29 (8)	C10—C9—C8	120.3 (3)
N1—Ni1—N3^i	158.38 (9)	C10—C9—H9	119.9
N6—Ni1—N3	160.44 (9)	C8—C9—H9	119.9
N2—Ni1—N3	94.69 (8)	N7—N6—Ni1	129.40 (19)
N1—Ni1—N3	92.73 (8)	C3—C4—C5	119.7 (2)
N3^i—Ni1—N3	76.09 (9)	C3—C4—H4	120.2
C2—N1—C13	118.9 (2)	C5—C4—H4	120.2
C2—N1—Ni1	129.23 (17)	C12—C8—C9	116.2 (3)
C13—N1—Ni1	111.79 (17)	C12—C8—C7	119.2 (3)
N2—C12—C8	123.2 (3)	C9—C8—C7	124.6 (3)
N2—C12—C13	117.6 (2)	N2—C11—C10	121.2 (2)
C8—C12—C13	119.3 (2)	N2—C11—C14	118.9 (2)
C11—N2—C12	118.8 (2)	C10—C11—C14	120.0 (2)
C11—N2—Ni1	129.58 (17)	C11—C14—H14A	109.5
C12—N2—Ni1	111.56 (16)	C11—C14—H14B	109.5
N1—C13—C5	122.5 (2)	H14A—C14—H14B	109.5
N1—C13—C12	116.9 (2)	C11—C14—H14C	109.5
C5—C13—C12	120.6 (2)	H14A—C14—H14C	109.5
N4—N3—Ni1^i	127.69 (16)	H14B—C14—H14C	109.5
N4—N3—Ni1	125.79 (15)	C9—C10—C11	120.3 (3)
Ni1^i—N3—Ni1	103.91 (9)	C9—C10—H10	119.9
N5—N4—N3	178.8 (3)	C11—C10—H10	119.9
C6—C7—C8	121.2 (3)	C7—C6—C5	121.5 (3)
C6—C7—H7	119.4	C7—C6—H6	119.3
C8—C7—H7	119.4	C5—C6—H6	119.3
N8—N7—N6	175.6 (3)	C2—C1—H1A	109.5
C4—C3—C2	120.7 (3)	C2—C1—H1B	109.5
C4—C3—H3	119.7	H1A—C1—H1B	109.5
C2—C3—H3	119.7	C2—C1—H1C	109.5
N1—C2—C3	121.0 (2)	H1A—C1—H1C	109.5
N1—C2—C1	118.1 (2)	H1B—C1—H1C	109.5
N6—Ni1—N1—C2	−73.3 (2)	C13—N1—C2—C3	1.7 (4)
N2—Ni1—N1—C2	−176.5 (2)	Ni1—N1—C2—C3	−174.51 (18)
N3^i—Ni1—N1—C2	31.3 (4)	C13—N1—C2—C1	−177.5 (2)
N3—Ni1—N1—C2	89.1 (2)	Ni1—N1—C2—C1	6.3 (3)
N6—Ni1—N1—C13	110.21 (17)	C4—C3—C2—N1	−0.4 (4)
N2—Ni1—N1—C13	7.01 (15)	C4—C3—C2—C1	178.8 (3)
N3^i—Ni1—N1—C13	−145.1 (2)	N1—C13—C5—C4	−0.3 (3)
N3—Ni1—N1—C13	−87.32 (16)	C12—C13—C5—C4	−177.6 (2)
C8—C12—N2—C11	0.9 (3)	N1—C13—C5—C6	178.8 (2)
C13—C12—N2—C11	−178.1 (2)	C12—C13—C5—C6	1.5 (3)
C8—C12—N2—Ni1	−177.34 (18)	N2—Ni1—N6—N7	76.4 (3)
C13—C12—N2—Ni1	3.7 (3)	N1—Ni1—N6—N7	−6.4 (3)
N6—Ni1—N2—C11	82.1 (2)	N3^i—Ni1—N6—N7	−165.5 (3)
N1—Ni1—N2—C11	176.2 (2)	N3—Ni1—N6—N7	−122.4 (3)
N3^i—Ni1—N2—C11	−14.9 (2)	C2—C3—C4—C5	−1.3 (4)
N3—Ni1—N2—C11	−91.7 (2)	C13—C5—C4—C3	1.6 (4)
N6—Ni1—N2—C12	−99.89 (16)	C6—C5—C4—C3	−177.4 (3)
N1—Ni1—N2—C12	−5.77 (15)	N2—C12—C8—C9	−1.8 (4)
N3^i—Ni1—N2—C12	163.06 (14)	C13—C12—C8—C9	177.1 (2)
N3—Ni1—N2—C12	86.31 (16)	N2—C12—C8—C7	178.9 (2)
C2—N1—C13—C5	−1.4 (3)	C13—C12—C8—C7	−2.2 (4)
Ni1—N1—C13—C5	175.47 (17)	C10—C9—C8—C12	0.7 (4)
C2—N1—C13—C12	176.0 (2)	C10—C9—C8—C7	179.9 (3)
Ni1—N1—C13—C12	−7.2 (3)	C6—C7—C8—C12	1.3 (4)
N2—C12—C13—N1	2.4 (3)	C6—C7—C8—C9	−178.0 (3)
C8—C12—C13—N1	−176.6 (2)	C12—N2—C11—C10	1.2 (4)
N2—C12—C13—C5	179.8 (2)	Ni1—N2—C11—C10	179.08 (19)
C8—C12—C13—C5	0.8 (3)	C12—N2—C11—C14	−179.7 (2)
N6—Ni1—N3—N4	152.5 (3)	Ni1—N2—C11—C14	−1.8 (4)
N2—Ni1—N3—N4	−45.8 (2)	C8—C9—C10—C11	1.3 (4)
N1—Ni1—N3—N4	36.0 (2)	N2—C11—C10—C9	−2.3 (4)
N3^i—Ni1—N3—N4	−162.8 (3)	C14—C11—C10—C9	178.6 (3)
N6—Ni1—N3—Ni1^i	−44.8 (3)	C8—C7—C6—C5	1.1 (4)
N2—Ni1—N3—Ni1^i	116.97 (10)	C4—C5—C6—C7	176.5 (3)
N1—Ni1—N3—Ni1^i	−161.26 (10)	C13—C5—C6—C7	−2.5 (4)
N3^i—Ni1—N3—Ni1^i	0.0

Symmetry code: (i) −x+3/2, −y+3/2, −z+2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C14—H14A···N3^i	0.96	2.47	3.391 (4)	162
C4—H4···N8^ii	0.93	2.43	3.304 (4)	157

Symmetry codes: (i) −x+3/2, −y+3/2, −z+2; (ii) −x+2, y, −z+3/2.