Cadmium binicotinate

The binicotinate dianion in cadmium binicotinate, [Cd(C₁₂H₆N₂O₄)], lies on a special position of 2 symmetry; the Cd atom lies on another special position of 2 symmetry. The carboxy CO₂ unit chelates to the Cd atom [Cd-O 2.304 (2) and 2.396 (2) Å]; the Cd atom is linked to one N atom of another binicotinate group [Cd-N1 2.315 (2) Å] and to the N atom of a third binicotinate group in a six-coordinate, distorted octahedral environment.

Key indicators

• Single-crystal X-ray study
• T = 294 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.019
• wR factor = 0.045
• Data-to-parameter ratio = 15.1

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT152_ALERT_1_C Supplied and Calc Volume s.u. Inconsistent .....          ?
PLAT804_ALERT_4_C ARU-Pack Problem in PLATON Analysis ............          !
PLAT804_ALERT_4_C ARU-Pack Problem in PLATON Analysis ............          !

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           28.20
           From the CIF: _reflns_number_total               1314
           Count of symmetry unique reflns          772
           Completeness (_total/calc)            170.21%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured       542
           Fraction of Friedel pairs measured     0.702
           Are heavy atom types Z>Si present          yes

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

   2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 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
   3 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97.

2,2'-Bipyridyl-3,3'-dicarboxylatocadmium(II)

Crystal data

[Cd(C12H6N2O4)]	Dx = 2.144 Mg m^−3
Mr = 354.59	Mo Kα radiation, λ = 0.71073 Å
Tetragonal, P4n2	Cell parameters from 2772 reflections
Hall symbol: P -4 -2n	θ = 3.5–28.2°
a = 8.1791 (6) Å	µ = 2.00 mm^−1
c = 16.420 (1) Å	T = 294 K
V = 1098.4 (1) Å^3	Needle, yellow
Z = 4	0.30 × 0.10 × 0.10 mm
F(000) = 688

Data collection

Bruker SMART APEX area-detector diffractometer	1314 independent reflections
Radiation source: fine-focus sealed tube	1276 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.020
φ and ω scan	θmax = 28.2°, θmin = 3.5°
Absorption correction: multi-scan (SADABS; Bruker, 2001)	h = −10→10
Tmin = 0.678, Tmax = 0.825	k = −9→8
4888 measured reflections	l = −21→15

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.019	H-atom parameters constrained
wR(F^2) = 0.045	w = 1/[σ^2(Fo^2) + (0.0236P)^2 + 0.1528P] where P = (Fo^2 + 2Fc^2)/3
S = 1.05	(Δ/σ)max = 0.001
1314 reflections	Δρmax = 0.37 e Å^−3
87 parameters	Δρmin = −0.35 e Å^−3
0 restraints	Absolute structure: Flack parameter from 548 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: −0.01 (3)

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

	x	y	z	Uiso*/Ueq
Cd1	0.71465 (2)	0.78535 (2)	0.7500	0.01865 (8)
N1	1.4751 (3)	0.8065 (2)	0.8244 (1)	0.0196 (4)
O1	0.8972 (2)	0.8095 (2)	0.8635 (1)	0.0318 (4)
O2	0.9953 (3)	0.7960 (2)	0.7387 (1)	0.0338 (5)
C1	1.3220 (5)	0.8087 (4)	0.7954 (1)	0.0161 (5)
C2	1.1858 (3)	0.8106 (3)	0.8475 (2)	0.0196 (5)
C3	1.2131 (3)	0.8108 (4)	0.9308 (2)	0.0259 (6)
C4	1.3711 (3)	0.8066 (3)	0.9603 (2)	0.0293 (6)
C5	1.4982 (3)	0.8037 (3)	0.9054 (2)	0.0251 (5)
C6	1.0142 (3)	0.8048 (3)	0.8144 (2)	0.0225 (5)
H3	1.1252	0.8138	0.9667	0.031*
H4	1.3912	0.8058	1.0161	0.035*
H5	1.6046	0.7996	0.9252	0.030*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cd1	0.0169 (1)	0.0169 (1)	0.0222 (1)	0.0003 (1)	0.0001 (1)	0.0001 (1)
N1	0.017 (1)	0.020 (1)	0.022 (1)	−0.001 (1)	−0.001 (1)	0.002 (1)
O1	0.018 (1)	0.045 (1)	0.033 (1)	0.000 (1)	0.004 (1)	−0.003 (1)
O2	0.019 (1)	0.058 (1)	0.025 (1)	−0.001 (1)	−0.003 (1)	0.007 (1)
C1	0.019 (2)	0.009 (1)	0.020 (1)	0.000 (1)	0.001 (1)	0.000 (1)
C2	0.017 (1)	0.020 (1)	0.021 (1)	0.000 (1)	0.001 (1)	0.000 (1)
C3	0.022 (1)	0.033 (2)	0.023 (1)	−0.003 (1)	0.005 (1)	0.001 (1)
C4	0.029 (2)	0.040 (2)	0.019 (1)	−0.004 (1)	−0.003 (1)	0.003 (1)
C5	0.022 (1)	0.032 (2)	0.022 (1)	0.000 (1)	−0.005 (1)	0.005 (1)
C6	0.018 (1)	0.015 (1)	0.034 (2)	0.000 (1)	−0.001 (1)	0.004 (1)

Geometric parameters (Å, º)

Cd1—O1	2.396 (2)	C1—C2	1.405 (4)
Cd1—O1^i	2.396 (2)	C1—C1^iv	1.498 (4)
Cd1—O2	2.304 (2)	C2—C3	1.386 (4)
Cd1—O2^i	2.304 (2)	C2—C6	1.506 (4)
Cd1—N1^ii	2.315 (2)	C3—C4	1.381 (4)
Cd1—N1^iii	2.315 (2)	C4—C5	1.376 (4)
N1—C1	1.339 (5)	C3—H3	0.93
N1—C5	1.344 (3)	C4—H4	0.93
O1—C6	1.251 (3)	C5—H5	0.93
O2—C6	1.256 (3)
O1—Cd1—O1^i	135.0 (1)	C6—O2—Cd1	92.6 (2)
O1—Cd1—O2	55.9 (1)	N1—C1—C2	121.6 (2)
O1—Cd1—O2^i	92.5 (1)	N1—C1—C1^iv	115.0 (3)
O1—Cd1—N1^ii	96.4 (1)	C2—C1—C1^iv	123.2 (4)
O1—Cd1—N1^iii	112.8 (1)	C3—C2—C1	118.3 (2)
O1^i—Cd1—O2	92.5 (1)	C3—C2—C6	120.4 (2)
O1^i—Cd1—O2^i	55.9 (1)	C1—C2—C6	121.3 (2)
O1^i—Cd1—N1^ii	112.8 (1)	C4—C3—C2	119.8 (2)
O1^i—Cd1—N1^iii	96.4 (1)	C5—C4—C3	118.5 (2)
O2—Cd1—O2^i	94.7 (1)	N1—C5—C4	122.8 (2)
O2—Cd1—N1^ii	152.0 (1)	O1—C6—O2	123.0 (3)
O2—Cd1—N1^iii	90.0 (1)	O1—C6—C2	118.7 (2)
O2^i—Cd1—N1^ii	90.0 (1)	O2—C6—C2	118.3 (2)
O2^i—Cd1—N1^iii	152.0 (1)	C4—C3—H3	120.1
N1^ii—Cd1—N1^iii	98.7 (1)	C2—C3—H3	120.1
C1—N1—C5	118.9 (2)	C5—C4—H4	120.7
C1—N1—Cd1^v	127.2 (2)	C3—C4—H4	120.7
C5—N1—Cd1^v	113.7 (2)	N1—C5—H5	118.6
C6—O1—Cd1	88.5 (2)	C4—C5—H5	118.6
O2^i—Cd1—O1—C6	93.0 (2)	N1—C1—C2—C6	−177.0 (3)
O2—Cd1—O1—C6	−1.1 (1)	C1^iv—C1—C2—C6	7.9 (6)
N1^ii—Cd1—O1—C6	−176.8 (2)	C1—C2—C3—C4	−1.0 (4)
N1^iii—Cd1—O1—C6	−74.5 (2)	C6—C2—C3—C4	176.3 (2)
O1^i—Cd1—O1—C6	51.7 (1)	C2—C3—C4—C5	0.5 (4)
O2^i—Cd1—O2—C6	−88.7 (1)	C1—N1—C5—C4	−1.5 (4)
N1^ii—Cd1—O2—C6	10.1 (2)	Cd1^v—N1—C5—C4	−176.7 (2)
N1^iii—Cd1—O2—C6	118.9 (2)	C3—C4—C5—N1	0.7 (4)
O1^i—Cd1—O2—C6	−144.7 (1)	Cd1—O1—C6—O2	1.9 (3)
O1—Cd1—O2—C6	1.0 (1)	Cd1—O1—C6—C2	−178.3 (2)
C5—N1—C1—C2	1.0 (4)	Cd1—O2—C6—O1	−2.0 (3)
Cd1^v—N1—C1—C2	175.5 (2)	Cd1—O2—C6—C2	178.3 (2)
C5—N1—C1—C1^iv	176.4 (3)	C3—C2—C6—O1	4.0 (4)
Cd1^v—N1—C1—C1^iv	−9.0 (5)	C1—C2—C6—O1	−178.9 (3)
N1—C1—C2—C3	0.2 (5)	C3—C2—C6—O2	−176.3 (2)
C1^iv—C1—C2—C3	−174.8 (4)	C1—C2—C6—O2	0.9 (4)

Symmetry codes: (i) −y+3/2, −x+3/2, −z+3/2; (ii) x−1, y, z; (iii) −y+3/2, −x+5/2, −z+3/2; (iv) y+1/2, x−1/2, −z+3/2; (v) x+1, y, z.