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In the title compound, [Cu2(μ-1,3-N3)(N3)2(phen)4](N3)·4H2O (phen is 1,10-phenanthroline, C12H8N2), each of the two Cu atoms is surrounded by two N atoms of two azide anions and by four N atoms of two 1,10-phenanthroline ligands [Cu—N distances are 1.964 (3), 2.009 (3), 2.018 (3), 2.054 (3), 2.306 (3) and 2.759 (4) Å], forming an elongated CuN6 octahedron. An ideally linear μ1,3-azide anion bridges two Cu atoms to form a dimeric structure with the central N atom located on a centre of inversion. Moreover, the adjacent dimeric units are connected by hydrogen-bond interactions to produce one-dimensional chains. A two-dimensional supramolecular array is formed by π–π interactions between the aromatic rings of 1,10-phenanthroline ligands of adjacent dimeric units.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270101016948/de1175sup1.cif
Contains datablocks I, global

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S0108270101016948/de1175Isup2.hkl
Contains datablock I

CCDC reference: 180128

Comment top

Studies on the synthesis and properties of bi- and polynuclear complexes bridged by the pseudohalide azide anion (N3-) have attracted a lot of attention in recent years (Ribas et al., 1999; Goher et al., 1998; Zhang et al., 2001), owing to their intriguing structural diversity, potential functions as models for metalloenzymes, and ferromagnetic or antiferromagnetic interactions (Baffert et al., 2001; Aebersold et al., 1998; Zhang et al., 2000). The azide anion can bind to metal ions in versatile modes: as a terminal ligand via one nitrogen donor, as a bridge in the µ1,1 way via one nitrogen donor, and in the µ1,3 way via both of the peripheral donor N atoms (Sheppard et al., 1996). Despite the fact that a substantial array of copper(II) azido complexes have been synthesized (Goher et al., 1999), to our knowledge, its dimeric single-bridged compounds with 1,10-phenanthroline have not been reported so far. We firstly report here the preparation and crystal structure of a dimeric azido complex of copper(II), namely [Cu2(phen)4(m1,3-azido)(N3)2](N3)·4H2O (I).

The molecular unit of the title compound comprises a dimeric cation [Cu2(phen)4(m1,3-azido)(N3)2]+, two azide anions and four water molecules. As shown in Fig. 1, the Cu atom is surrounded by two N atoms of two azide anions and four N atoms of two 1,10-phenanthroline ligands to form a elongated CuN6 octahedron. The Cu—N bond lengths in apical positions [2.306 (3), 2.759 (4) Å] are much longer than the Cu—N bond lengths in equatorial positions [1.964 (3), 2.009 (3), 2.018 (3), 2.054 (3) Å], due to the Jahn-Teller effects of CuII. An ideally linear µ1,3-azide anion bridges two Cu atoms to form a dimeric entity with N2 located on a centre of inversion, with the Cu···Cu distance at 6.783 (4) Å.

It should be noted that hydrogen bonding interactions and π-π interactions play an important role in the solid state structure of (I), as shown in Fig. 2. The adjacent dimeric units are connected by hydrogen-bond interactions (O1w···O2w, O1w···N10, O1w···N1, C9···N10I) [2.857 (5), 2.792 (6), 2.908 (5), 3.411 (7) Å], to produce chains. It is interesting that there are interchain π-π interactions between the 1,10-phenanthroline rings of adjacent chains with the face-to-face separation of ca 3.47 Å, which is different from other related compounds (Diaz et al., 2001), resulting in an interesting two-dimensional structure.

Experimental top

A mixture of 1.0 mmol of copper(II) nitrate hexahydrate, 2 mmol of 1,10-phenanthroline and 2 mmol sodium azide in 60 ml mixed solvent of water and ethanol(volume 2:1) is stirred for 30 min at room temperature. After four days, dark green crystals of the title compound are obtained in 85% yield.

Refinement top

Also, all the H atoms have been constrained and all constrained C—H distances were 0.94 Å.

Computing details top

Data collection: SMART1000 (Bruker, 1998); cell refinement: SMART1000; data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Sheldrick, 1998); software used to prepare material for publication: SHELXL97.

Figures top
[Figure 1] Fig. 1. ORTEP (Sheldrick, 1998) plot (50% probability displacement ellipsoids) of the coordination environment in the title compound [Symmetry code: (i) -x, -y, 1 - z].
[Figure 2] Fig. 2. Crystal structure of the title compound (I).
Diazido µ1,3-azidotetra(1,10-phenanthroline) diCopper(II) azide tetrahydrate top
Crystal data top
[Cu2(C12H8N2)4(N3)3]·N3·4H2OZ = 1
Mr = 1088.08F(000) = 558
Triclinic, P1Dx = 1.529 Mg m3
a = 8.676 (5) ÅMo Kα radiation, λ = 0.71073 Å
b = 11.843 (8) Åθ = 1.5–24.3°
c = 12.279 (8) ŵ = 0.97 mm1
α = 80.81 (1)°T = 293 K
β = 71.74 (1)°Block, dark green
γ = 84.60 (1)°0.20 × 0.15 × 0.12 mm
V = 1181.4 (13) Å3
Data collection top
CCD area detector
diffractometer
4133 independent reflections
Radiation source: fine-focus sealed tube3239 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.021
ω scansθmax = 25.0°, θmin = 1.7°
Absorption correction: empirical (using intensity measurements)
(SADABS; Sheldrick 1996)
h = 910
Tmin = 0.858, Tmax = 0.890k = 1413
6191 measured reflectionsl = 1412
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.046Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.121H atoms treated by a mixture of independent and constrained refinement
S = 1.03Calculated w = 1/[σ2(Fo2) + (0.0587P)2 + 0.7136P]
where P = (Fo2 + 2Fc2)/3
4133 reflections(Δ/σ)max < 0.001
337 parametersΔρmax = 0.37 e Å3
0 restraintsΔρmin = 0.43 e Å3
Crystal data top
[Cu2(C12H8N2)4(N3)3]·N3·4H2Oγ = 84.60 (1)°
Mr = 1088.08V = 1181.4 (13) Å3
Triclinic, P1Z = 1
a = 8.676 (5) ÅMo Kα radiation
b = 11.843 (8) ŵ = 0.97 mm1
c = 12.279 (8) ÅT = 293 K
α = 80.81 (1)°0.20 × 0.15 × 0.12 mm
β = 71.74 (1)°
Data collection top
CCD area detector
diffractometer
4133 independent reflections
Absorption correction: empirical (using intensity measurements)
(SADABS; Sheldrick 1996)
3239 reflections with I > 2σ(I)
Tmin = 0.858, Tmax = 0.890Rint = 0.021
6191 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0460 restraints
wR(F2) = 0.121H atoms treated by a mixture of independent and constrained refinement
S = 1.03Δρmax = 0.37 e Å3
4133 reflectionsΔρmin = 0.43 e Å3
337 parameters
Special details top

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 > σ(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 (Å2) top
xyzUiso*/Ueq
Cu10.12897 (5)0.26244 (4)0.36525 (3)0.04023 (16)
N10.0460 (4)0.0373 (3)0.4007 (4)0.0671 (10)
N20.00000.00000.50000.0552 (12)
N30.1025 (4)0.3100 (3)0.4176 (3)0.0519 (8)
N40.1658 (4)0.3764 (3)0.3619 (3)0.0631 (9)
N50.2339 (7)0.4393 (6)0.3104 (4)0.143 (3)
N60.1401 (3)0.2288 (2)0.5283 (2)0.0378 (6)
N70.3610 (3)0.1903 (2)0.3309 (2)0.0373 (6)
N80.2513 (4)0.4353 (3)0.3252 (2)0.0444 (7)
N90.1444 (3)0.3108 (3)0.1971 (2)0.0414 (7)
N100.1188 (7)0.0298 (6)0.0179 (4)0.122 (2)
N110.00000.00000.00000.0647 (13)
C10.0247 (4)0.2452 (3)0.6260 (3)0.0485 (9)
H1A0.08210.27130.62250.080*
C20.0546 (5)0.2263 (4)0.7328 (3)0.0570 (10)
H2A0.03170.23870.80190.080*
C30.2056 (5)0.1903 (4)0.7385 (3)0.0540 (10)
H3A0.22750.17680.81150.080*
C40.3316 (4)0.1724 (3)0.6369 (3)0.0410 (8)
C50.2910 (4)0.1926 (3)0.5339 (3)0.0346 (7)
C60.4114 (4)0.1739 (3)0.4268 (3)0.0362 (7)
C70.5701 (4)0.1392 (3)0.4262 (3)0.0417 (8)
C80.6827 (4)0.1209 (3)0.3181 (3)0.0511 (9)
H8A0.79400.09890.31240.080*
C90.6312 (5)0.1356 (3)0.2223 (4)0.0568 (10)
H9A0.70680.12220.14900.080*
C100.4690 (4)0.1699 (3)0.2317 (3)0.0478 (9)
H10A0.43470.17940.16350.080*
C110.6092 (4)0.1214 (3)0.5328 (4)0.0500 (9)
H11A0.71850.09800.53210.080*
C120.4942 (5)0.1366 (3)0.6333 (3)0.0486 (9)
H12A0.52310.12350.70380.080*
C130.3111 (5)0.4915 (3)0.3864 (4)0.0535 (10)
H13A0.29730.46140.46610.080*
C140.3920 (5)0.5926 (4)0.3411 (4)0.0611 (11)
H14A0.43710.62970.38740.080*
C150.4093 (5)0.6377 (4)0.2294 (4)0.0635 (11)
H15A0.46310.70820.19760.080*
C160.3453 (4)0.5814 (3)0.1606 (3)0.0509 (9)
C170.2696 (4)0.4784 (3)0.2130 (3)0.0411 (8)
C180.2102 (4)0.4137 (3)0.1462 (3)0.0414 (8)
C190.2197 (4)0.4579 (3)0.0306 (3)0.0500 (9)
C200.1561 (5)0.3930 (4)0.0302 (3)0.0604 (11)
H20A0.16180.41980.10940.080*
C210.0873 (5)0.2920 (4)0.0232 (3)0.0581 (11)
H21A0.04080.24810.01700.080*
C220.0854 (4)0.2528 (4)0.1366 (3)0.0487 (9)
H22A0.03840.18090.17310.080*
C230.2941 (5)0.5659 (4)0.0181 (4)0.0649 (12)
H23A0.30330.59500.09740.080*
C240.3527 (5)0.6238 (4)0.0438 (4)0.0638 (12)
H24A0.39960.69620.00950.080*
O1W0.2627 (4)0.0484 (4)0.1944 (3)0.0935 (11)
H1WA0.26580.00610.12920.080*
H1WB0.26230.01570.25940.080*
O2W0.5689 (4)0.1273 (3)0.0509 (3)0.0857 (10)
H2WA0.64430.06940.02680.080*
H2WB0.46930.10060.09890.080*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cu10.0360 (2)0.0507 (3)0.0323 (2)0.00122 (18)0.00952 (17)0.00420 (18)
N10.056 (2)0.072 (3)0.077 (3)0.0026 (19)0.020 (2)0.024 (2)
N20.033 (2)0.056 (3)0.085 (4)0.008 (2)0.024 (3)0.030 (3)
N30.0397 (17)0.067 (2)0.0435 (17)0.0062 (15)0.0103 (14)0.0003 (16)
N40.054 (2)0.082 (3)0.0475 (19)0.0219 (19)0.0130 (17)0.0117 (18)
N50.128 (5)0.191 (6)0.084 (3)0.094 (4)0.036 (3)0.007 (4)
N60.0369 (15)0.0404 (16)0.0351 (15)0.0008 (12)0.0097 (12)0.0051 (12)
N70.0365 (15)0.0392 (16)0.0332 (15)0.0031 (12)0.0057 (12)0.0055 (12)
N80.0482 (17)0.0431 (17)0.0418 (17)0.0021 (13)0.0136 (14)0.0059 (13)
N90.0379 (15)0.0498 (18)0.0357 (15)0.0014 (13)0.0111 (12)0.0054 (13)
N100.088 (4)0.198 (7)0.072 (3)0.020 (4)0.022 (3)0.016 (3)
N110.071 (4)0.075 (4)0.042 (3)0.002 (3)0.006 (3)0.017 (2)
C10.040 (2)0.060 (2)0.039 (2)0.0023 (17)0.0048 (16)0.0067 (17)
C20.056 (2)0.076 (3)0.034 (2)0.006 (2)0.0069 (17)0.0130 (19)
C30.063 (3)0.064 (3)0.038 (2)0.002 (2)0.0195 (18)0.0100 (18)
C40.048 (2)0.0357 (19)0.044 (2)0.0021 (15)0.0187 (16)0.0062 (15)
C50.0384 (18)0.0307 (17)0.0352 (17)0.0040 (13)0.0106 (14)0.0061 (13)
C60.0342 (17)0.0298 (17)0.0440 (19)0.0029 (13)0.0110 (15)0.0045 (14)
C70.0355 (18)0.0356 (19)0.053 (2)0.0043 (14)0.0114 (16)0.0048 (15)
C80.038 (2)0.048 (2)0.062 (3)0.0009 (16)0.0087 (18)0.0068 (18)
C90.049 (2)0.053 (2)0.053 (2)0.0005 (18)0.0068 (19)0.0087 (19)
C100.046 (2)0.050 (2)0.042 (2)0.0022 (17)0.0046 (16)0.0062 (16)
C110.041 (2)0.045 (2)0.071 (3)0.0026 (16)0.0274 (19)0.0080 (19)
C120.056 (2)0.044 (2)0.055 (2)0.0006 (17)0.0288 (19)0.0082 (17)
C130.058 (2)0.048 (2)0.056 (2)0.0011 (19)0.0187 (19)0.0131 (18)
C140.065 (3)0.050 (2)0.072 (3)0.006 (2)0.020 (2)0.016 (2)
C150.060 (3)0.043 (2)0.078 (3)0.0114 (19)0.007 (2)0.005 (2)
C160.047 (2)0.042 (2)0.052 (2)0.0039 (17)0.0026 (18)0.0012 (17)
C170.0364 (18)0.040 (2)0.0398 (19)0.0062 (15)0.0048 (15)0.0048 (15)
C180.0326 (17)0.050 (2)0.0363 (18)0.0100 (15)0.0070 (14)0.0039 (16)
C190.044 (2)0.061 (2)0.0365 (19)0.0122 (18)0.0080 (16)0.0009 (17)
C200.060 (3)0.082 (3)0.036 (2)0.022 (2)0.0153 (19)0.009 (2)
C210.056 (2)0.080 (3)0.043 (2)0.015 (2)0.0188 (19)0.024 (2)
C220.043 (2)0.062 (2)0.044 (2)0.0039 (17)0.0163 (17)0.0144 (18)
C230.065 (3)0.066 (3)0.044 (2)0.015 (2)0.002 (2)0.010 (2)
C240.064 (3)0.050 (3)0.060 (3)0.001 (2)0.004 (2)0.012 (2)
O1W0.065 (2)0.132 (3)0.088 (2)0.003 (2)0.0223 (19)0.037 (2)
O2W0.076 (2)0.074 (2)0.086 (2)0.0002 (17)0.0029 (18)0.0050 (18)
Geometric parameters (Å, º) top
Cu1—N31.964 (3)C3—C41.408 (5)
Cu1—N62.009 (3)C4—C51.396 (5)
Cu1—N92.018 (3)C4—C121.424 (5)
Cu1—N72.054 (3)C5—C61.435 (5)
Cu1—N82.306 (3)C6—C71.397 (5)
Cu1—N12.759 (4)C7—C81.416 (5)
N1—N21.182 (4)C7—C111.431 (5)
N1—O1W2.908 (5)C8—C91.365 (6)
N2—N1i1.182 (4)C9—C101.402 (5)
N3—N41.171 (4)C9—N10iii3.411 (7)
N4—N51.142 (5)C11—C121.348 (5)
N6—C11.329 (4)C13—C141.392 (6)
N6—C51.358 (4)C14—C151.358 (6)
N7—C101.325 (4)C15—C161.417 (6)
N7—C61.360 (4)C16—C171.403 (5)
N8—C131.321 (5)C16—C241.426 (6)
N8—C171.355 (4)C17—C181.437 (5)
N9—C221.325 (5)C18—C191.412 (5)
N9—C181.366 (5)C19—C201.405 (6)
N10—N111.133 (6)C19—C231.442 (6)
N10—O1W2.792 (6)C20—C211.363 (6)
N11—N10ii1.133 (6)C21—C221.391 (5)
C1—C21.396 (5)C23—C241.335 (6)
C2—C31.358 (6)O1W—O2W2.857 (5)
N3—Cu1—N692.21 (12)C3—C4—C12124.5 (3)
N3—Cu1—N992.55 (12)N6—C5—C4123.5 (3)
N6—Cu1—N9171.83 (11)N6—C5—C6116.6 (3)
N3—Cu1—N7170.71 (12)C4—C5—C6120.0 (3)
N6—Cu1—N781.49 (11)N7—C6—C7124.0 (3)
N9—Cu1—N794.53 (11)N7—C6—C5116.6 (3)
N3—Cu1—N8101.94 (13)C7—C6—C5119.4 (3)
N6—Cu1—N894.74 (11)C6—C7—C8116.7 (3)
N9—Cu1—N877.76 (11)C6—C7—C11119.4 (3)
N7—Cu1—N885.46 (11)C8—C7—C11123.8 (3)
N3—Cu1—N189.61 (13)C9—C8—C7119.2 (3)
N6—Cu1—N184.32 (12)C8—C9—C10119.9 (4)
N9—Cu1—N1102.36 (12)C8—C9—N10iii117.3 (3)
N7—Cu1—N183.02 (11)C10—C9—N10iii121.4 (3)
N8—Cu1—N1168.45 (11)N7—C10—C9122.6 (4)
N2—N1—Cu1112.5 (2)C12—C11—C7120.6 (3)
N2—N1—O1W134.6 (3)C11—C12—C4121.4 (3)
Cu1—N1—O1W102.11 (16)N8—C13—C14123.1 (4)
N1i—N2—N1180.0C15—C14—C13119.3 (4)
N4—N3—Cu1123.4 (3)C14—C15—C16119.7 (4)
N5—N4—N3177.0 (5)C17—C16—C15116.9 (4)
C1—N6—C5118.3 (3)C17—C16—C24119.2 (4)
C1—N6—Cu1128.5 (2)C15—C16—C24123.9 (4)
C5—N6—Cu1113.0 (2)N8—C17—C16122.7 (3)
C10—N7—C6117.5 (3)N8—C17—C18117.7 (3)
C10—N7—Cu1130.7 (2)C16—C17—C18119.7 (3)
C6—N7—Cu1111.3 (2)N9—C18—C19121.6 (3)
C13—N8—C17118.3 (3)N9—C18—C17118.8 (3)
C13—N8—Cu1132.9 (3)C19—C18—C17119.6 (3)
C17—N8—Cu1108.6 (2)C20—C19—C18117.6 (4)
C22—N9—C18118.7 (3)C20—C19—C23124.0 (4)
C22—N9—Cu1124.0 (3)C18—C19—C23118.5 (4)
C18—N9—Cu1117.1 (2)C21—C20—C19119.9 (4)
N11—N10—O1W140.3 (4)C20—C21—C22119.3 (4)
N10ii—N11—N10180.0N9—C22—C21122.9 (4)
N6—C1—C2121.9 (3)C24—C23—C19121.4 (4)
C3—C2—C1119.7 (4)C23—C24—C16121.5 (4)
C2—C3—C4120.2 (3)N10—O1W—O2W92.79 (17)
C5—C4—C3116.4 (3)N10—O1W—N1112.09 (18)
C5—C4—C12119.1 (3)O2W—O1W—N1154.61 (17)
Symmetry codes: (i) x, y, z+1; (ii) x, y, z; (iii) x+1, y, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1WA···N100.942.252.792 (6)116
O1W—H1WB···N10.942.242.908 (5)128
O2W—H2WB···O1W0.941.922.857 (5)178
C9—H9A···N10iii0.942.503.411 (7)163
Symmetry code: (iii) x+1, y, z.

Experimental details

Crystal data
Chemical formula[Cu2(C12H8N2)4(N3)3]·N3·4H2O
Mr1088.08
Crystal system, space groupTriclinic, P1
Temperature (K)293
a, b, c (Å)8.676 (5), 11.843 (8), 12.279 (8)
α, β, γ (°)80.81 (1), 71.74 (1), 84.60 (1)
V3)1181.4 (13)
Z1
Radiation typeMo Kα
µ (mm1)0.97
Crystal size (mm)0.20 × 0.15 × 0.12
Data collection
DiffractometerCCD area detector
diffractometer
Absorption correctionEmpirical (using intensity measurements)
(SADABS; Sheldrick 1996)
Tmin, Tmax0.858, 0.890
No. of measured, independent and
observed [I > 2σ(I)] reflections
6191, 4133, 3239
Rint0.021
(sin θ/λ)max1)0.596
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.046, 0.121, 1.03
No. of reflections4133
No. of parameters337
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.37, 0.43

Computer programs: SMART1000 (Bruker, 1998), SMART1000, SAINT (Bruker, 1998), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL (Sheldrick, 1998), SHELXL97.

Selected geometric parameters (Å, º) top
Cu1—N31.964 (3)Cu1—N82.306 (3)
Cu1—N62.009 (3)Cu1—N12.759 (4)
Cu1—N92.018 (3)N1—O1W2.908 (5)
Cu1—N72.054 (3)O1W—O2W2.857 (5)
N3—Cu1—N692.21 (12)N3—Cu1—N189.61 (13)
N3—Cu1—N992.55 (12)N6—Cu1—N184.32 (12)
N6—Cu1—N9171.83 (11)N9—Cu1—N1102.36 (12)
N3—Cu1—N7170.71 (12)N7—Cu1—N183.02 (11)
N6—Cu1—N781.49 (11)N8—Cu1—N1168.45 (11)
N9—Cu1—N794.53 (11)N2—N1—Cu1112.5 (2)
N3—Cu1—N8101.94 (13)N4—N3—Cu1123.4 (3)
N6—Cu1—N894.74 (11)N10—O1W—O2W92.79 (17)
N9—Cu1—N877.76 (11)N10—O1W—N1112.09 (18)
N7—Cu1—N885.46 (11)O2W—O1W—N1154.61 (17)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1WA···N100.942.252.792 (6)116.1
O1W—H1WB···N10.942.242.908 (5)127.5
O2W—H2WB···O1W0.941.922.857 (5)178.2
C9—H9A···N10i0.942.503.411 (7)163.4
Symmetry code: (i) x+1, y, z.
 

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