catena-Poly[[(isonicotinato)uran­yl(VI)]-μ-oxalato]

The repeat unit of the title compound, [U(C₆H₅NO₂)(C₂O₄)O₂]_n, consists of a uranyl unit, an oxalate anion and a zwitterionic isonicotinic acid. The U atoms and the isonicotinic acid ligand are located on a crystallographic twofold rotation axis, while the oxalate lies on an inversion centre. Each UO₂ unit is coordinated by two oxalate ligands and one isonicotinic ligand. In the crystal structure, the UO₈ hexa­gonal bipyramids are connected by oxalate groups to form chains, and adjacent chains are linked into two-dimensional sheets by bifurcated N—H...O hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.008 Å
• R factor = 0.026
• wR factor = 0.058
• Data-to-parameter ratio = 15.6

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low .......       0.97
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.87
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.78
PLAT369_ALERT_2_C Long   C(sp2)-C(sp2) Bond  C1     -   C1_b   ...       1.54 Ang.
PLAT764_ALERT_4_C Overcomplete CIF Bond List Detected (Rep/Expd) .       1.17 Ratio

Alert level G
ABSTM02_ALERT_3_G  When printed, the submitted absorption T values will be
            replaced by the scaled T values. Since the ratio of scaled T's
            is identical to the ratio of reported T values, the scaling
            does not imply a change to the absorption corrections used in
            the study.
            Ratio of Tmax expected/reported      0.870
            Tmax scaled      0.404 Tmin scaled      0.150

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   5 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
   2 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: enCIFer (Allen et al., 2004) and PLATON (Spek, 2003).

catena-Poly[[(isonicotinato)uranyl(VI)]-µ-oxalato]

Crystal data

[U(C6H5NO2)(C2O4)O2]	F(000) = 864
Mr = 481.16	Dx = 2.965 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 25 reflections
a = 10.6836 (12) Å	θ = 12–18°
b = 11.8752 (14) Å	µ = 15.09 mm^−1
c = 9.0111 (11) Å	T = 298 K
β = 109.460 (2)°	Needle-like, yellow
V = 1077.9 (2) Å^3	0.18 × 0.07 × 0.06 mm
Z = 4

Data collection

Bruker SMART APEX-II CCD diffractometer	1314 independent reflections
Radiation source: fine-focus sealed tube	1075 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.036
φ and ω scans	θmax = 28.4°, θmin = 2.7°
Absorption correction: multi-scan (SADABS; Sheldrick, 2003)	h = −14→13
Tmin = 0.172, Tmax = 0.465	k = −15→15
3946 measured reflections	l = −11→11

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)] = 0.026	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.058	H-atom parameters constrained
S = 0.99	w = 1/[σ^2(Fo^2) + (0.0324P)^2] where P = (Fo^2 + 2Fc^2)/3
1314 reflections	(Δ/σ)max < 0.001
84 parameters	Δρmax = 2.24 e Å^−3
0 restraints	Δρmin = −1.65 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 > 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 (Ų)

	x	y	z	Uiso*/Ueq
U1	0.0000	0.37418 (2)	0.2500	0.02295 (10)
O1	−0.2182 (4)	0.3907 (3)	0.0423 (5)	0.0365 (10)
O2	−0.3842 (4)	0.3063 (3)	−0.1456 (5)	0.0365 (10)
O3	−0.1085 (4)	0.5655 (3)	0.2169 (5)	0.0359 (10)
O4	0.0671 (4)	0.3678 (3)	0.0993 (5)	0.0340 (9)
N1	0.0000	0.9703 (6)	0.2500	0.046 (2)
H1	0.0000	1.0427	0.2500	0.055*
C1	−0.2809 (6)	0.3075 (4)	−0.0315 (7)	0.0287 (12)
C2	0.0000	0.6159 (6)	0.2500	0.0286 (16)
C3	0.0000	0.7431 (6)	0.2500	0.0285 (17)
C4	−0.1189 (6)	0.8012 (5)	0.1926 (8)	0.0365 (14)
H4	−0.1990	0.7626	0.1537	0.044*
C5	−0.1160 (8)	0.9173 (6)	0.1942 (9)	0.0470 (17)
H5	−0.1945	0.9582	0.1566	0.056*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
U1	0.02092 (15)	0.01424 (13)	0.02561 (17)	0.000	−0.00300 (10)	0.000
O1	0.031 (2)	0.0174 (19)	0.043 (3)	0.0011 (16)	−0.0111 (18)	−0.0021 (16)
O2	0.031 (2)	0.0206 (19)	0.037 (2)	−0.0004 (16)	−0.0160 (18)	0.0013 (16)
O3	0.037 (3)	0.0177 (19)	0.046 (3)	−0.0047 (17)	0.005 (2)	−0.0007 (17)
O4	0.036 (2)	0.032 (2)	0.027 (2)	0.0003 (19)	0.0008 (17)	−0.0035 (17)
N1	0.050 (5)	0.013 (3)	0.078 (6)	0.000	0.024 (5)	0.000
C1	0.026 (3)	0.017 (2)	0.034 (3)	−0.001 (2)	−0.001 (2)	0.002 (2)
C2	0.038 (4)	0.019 (4)	0.023 (4)	0.000	0.002 (3)	0.000
C3	0.035 (5)	0.013 (3)	0.034 (5)	0.000	0.005 (4)	0.000
C4	0.027 (3)	0.027 (3)	0.049 (4)	−0.003 (2)	0.003 (3)	0.003 (3)
C5	0.046 (4)	0.027 (3)	0.065 (5)	0.006 (3)	0.014 (4)	0.013 (3)

Geometric parameters (Å, º)

U1—O4	1.736 (4)	O3—C2	1.249 (5)
U1—O4^i	1.736 (4)	N1—C5	1.330 (8)
U1—O1	2.463 (4)	N1—C5^i	1.330 (8)
U1—O1^i	2.463 (4)	N1—H1	0.8600
U1—O2^ii	2.497 (4)	C1—C1^ii	1.539 (10)
U1—O2^iii	2.497 (4)	C2—O3^i	1.249 (5)
U1—O3^i	2.522 (4)	C2—C3	1.511 (10)
U1—O3	2.522 (4)	C3—C4^i	1.385 (7)
U1—C2	2.870 (7)	C3—C4	1.385 (7)
O1—C1	1.254 (6)	C4—C5	1.379 (9)
O2—C1	1.233 (7)	C4—H4	0.9300
O2—U1^ii	2.497 (4)	C5—H5	0.9300
O4—U1—O4^i	175.0 (2)	O1—U1—C2	85.42 (8)
O4—U1—O1	86.66 (18)	O1^i—U1—C2	85.42 (8)
O4^i—U1—O1	93.74 (18)	O2^ii—U1—C2	149.15 (9)
O4—U1—O1^i	93.74 (18)	O2^iii—U1—C2	149.15 (9)
O4^i—U1—O1^i	86.66 (18)	O3^i—U1—C2	25.76 (10)
O1—U1—O1^i	170.85 (16)	O3—U1—C2	25.76 (10)
O4—U1—O2^ii	87.11 (16)	C1—O1—U1	122.9 (3)
O4^i—U1—O2^ii	88.59 (16)	C1—O2—U1^ii	121.1 (4)
O1—U1—O2^ii	63.75 (12)	C2—O3—U1	92.9 (4)
O1^i—U1—O2^ii	125.40 (12)	C5—N1—C5^i	123.5 (8)
O4—U1—O2^iii	88.59 (16)	C5—N1—H1	118.2
O4^i—U1—O2^iii	87.11 (16)	C5^i—N1—H1	118.2
O1—U1—O2^iii	125.40 (12)	O2—C1—O1	128.5 (5)
O1^i—U1—O2^iii	63.75 (12)	O2—C1—C1^ii	116.9 (6)
O2^ii—U1—O2^iii	61.70 (18)	O1—C1—C1^ii	114.6 (6)
O4—U1—O3^i	80.73 (16)	O3—C2—O3^i	122.7 (7)
O4^i—U1—O3^i	103.88 (16)	O3—C2—C3	118.6 (4)
O1—U1—O3^i	107.41 (13)	O3^i—C2—C3	118.6 (4)
O1^i—U1—O3^i	63.71 (13)	O3—C2—U1	61.4 (4)
O2^ii—U1—O3^i	165.52 (13)	O3^i—C2—U1	61.4 (4)
O2^iii—U1—O3^i	125.32 (14)	C3—C2—U1	180.000 (1)
O4—U1—O3	103.88 (16)	C4^i—C3—C4	120.3 (7)
O4^i—U1—O3	80.73 (15)	C4^i—C3—C2	119.8 (4)
O1—U1—O3	63.71 (13)	C4—C3—C2	119.8 (4)
O1^i—U1—O3	107.41 (13)	C5—C4—C3	118.6 (6)
O2^ii—U1—O3	125.32 (14)	C5—C4—H4	120.7
O2^iii—U1—O3	165.51 (13)	C3—C4—H4	120.7
O3^i—U1—O3	51.51 (19)	N1—C5—C4	119.4 (7)
O4—U1—C2	92.51 (12)	N1—C5—H5	120.3
O4^i—U1—C2	92.51 (12)	C4—C5—H5	120.3

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O2^iv	0.86	2.20	2.946 (7)	145

Symmetry code: (iv) −x−1/2, −y+3/2, −z.