Crystal structure of poly[[hexa­aqua­tris­(μ-3,6-di­oxo­cyclo­hexa-1,4-diene-1,4-diolato)dierbium(III)] octa­deca­hydrate]

The title lanthanide complex is isostructural with its La, Gd, Yb and Lu analogues. The Er³⁺ ion, located on a threefold rotation axis, is nine-coordinated in a distorted tricapped trigonal–prismatic geometry, which is completed by six oxygen atoms from three dhbq²⁻ ligands and three oxygen atoms from coordinated water mol­ecules. Each dhbq²⁻ ligand acts as a μ₂-bis­(bidentate) bridging mode to connect two Er³⁺ ions to form honeycomb (6,3) two-dimensional sheets extending in the ab plane.

Key indicators

• Single-crystal X-ray study
• T = 296 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.023
• wR factor = 0.042
• Data-to-parameter ratio = 21.4

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT601_ALERT_2_C Structure Contains Solvent Accessible VOIDS of .         40 Ang   3
PLAT905_ALERT_3_C Negative K value in the Analysis of Variance ...     -0.417 Report
PLAT925_ALERT_1_C The Reported and Calculated Rho(max) Differ by .       1.06 eA-3
PLAT975_ALERT_2_C Check Calcd Resid. Dens.  0.89A   From O4              0.41 eA-3
PLAT978_ALERT_2_C Number C-C Bonds with Positive Residual Density.          0 Info

Alert level G
PLAT004_ALERT_5_G Polymeric Structure Found with Maximum Dimension          2 Info
PLAT005_ALERT_5_G No Embedded Refinement Details Found  in the CIF     Please Do !
PLAT042_ALERT_1_G Calc. and Reported MoietyFormula Strings  Differ     Please Check
PLAT045_ALERT_1_G Calculated and Reported Z Differ by a Factor ...       2.00 Check
PLAT083_ALERT_2_G SHELXL Second Parameter in WGHT  Unusually Large      10.26 Why ?
PLAT152_ALERT_1_G The Supplied and Calc. Volume s.u. Differ by ...          5 Units
PLAT333_ALERT_2_G Large Aver C6-Ring C-C Dist C1       -C3_c     .       1.45 Ang.
PLAT794_ALERT_5_G Tentative Bond Valency for Er1       (III)     .       3.03 Info
PLAT860_ALERT_3_G Number of Least-Squares Restraints .............          8 Note
PLAT910_ALERT_3_G Missing # of FCF Reflection(s) Below Theta(Min).          1 Note

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   5 ALERT level C = Check. Ensure it is not caused by an omission or oversight
  10 ALERT level G = General information/check it is not something unexpected

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

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Computing details

Data collection: APEX3 (Bruker, 2016); cell refinement: SAINT (Bruker, 2016); data reduction: SAINT (Bruker, 2016); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL (Sheldrick, 2015b); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

Poly[[hexaaquatris(µ-3,6-dioxocyclohexa-1,4-diene-1,4-diolato)dierbium(III)] octadecahydrate]

Crystal data

[Er2(C6H2O4)3(H2O)6]·18H2O	Dx = 1.894 Mg m^−3
Mr = 1181.13	Mo Kα radiation, λ = 0.71073 Å
Trigonal, R3	Cell parameters from 8655 reflections
a = 14.0947 (3) Å	θ = 2.8–31.7°
c = 18.0603 (5) Å	µ = 4.13 mm^−1
V = 3107.18 (13) Å^3	T = 296 K
Z = 3	Hexagonal prism, dark red
F(000) = 1758	0.28 × 0.22 × 0.2 mm

Data collection

Bruker D8 QUEST CMOS diffractometer	2522 independent reflections
Radiation source: microfocus sealed x-ray tube, Incoatec Iµus	2108 reflections with I > 2σ(I)
GraphiteDouble Bounce Multilayer Mirror monochromator	Rint = 0.065
Detector resolution: 10.5 pixels mm^-1	θmax = 32.6°, θmin = 2.8°
φ and ω scans	h = −21→21
Absorption correction: multi-scan (SADABS; Bruker, 2016)	k = −19→21
Tmin = 0.677, Tmax = 0.746	l = −27→27
32360 measured reflections

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)] = 0.023	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.042	w = 1/[σ^2(Fo^2) + (0.0042P)^2 + 10.2637P] where P = (Fo^2 + 2Fc^2)/3
S = 1.08	(Δ/σ)max = 0.001
2522 reflections	Δρmax = 1.67 e Å^−3
118 parameters	Δρmin = −1.39 e Å^−3
8 restraints	Extinction correction: SHELXL (Sheldrick, 2015b), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: dual	Extinction coefficient: 0.00020 (2)

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
Er1	0.6667	0.3333	0.587213 (10)	0.01773 (5)
O1	0.65928 (12)	0.50374 (13)	0.58327 (9)	0.0236 (3)
O2	0.54678 (13)	0.33698 (13)	0.49769 (9)	0.0247 (3)
O3	0.54011 (16)	0.33067 (15)	0.67424 (11)	0.0355 (4)
H3A	0.557 (3)	0.3878 (16)	0.6975 (16)	0.055 (10)*
H3B	0.4856 (17)	0.2781 (17)	0.6941 (15)	0.046 (9)*
O4	0.7266 (2)	0.52214 (19)	0.37540 (12)	0.0455 (5)
H4A	0.736 (3)	0.494 (3)	0.4136 (13)	0.075 (13)*
H4B	0.6643 (16)	0.489 (3)	0.356 (2)	0.079 (14)*
O5	0.29245 (18)	0.15371 (19)	0.57009 (14)	0.0452 (5)
H5A	0.354 (2)	0.167 (5)	0.587 (3)	0.15 (2)*
H5B	0.285 (4)	0.138 (4)	0.5247 (8)	0.103 (17)*
O6	0.18028 (19)	0.2663 (2)	0.57759 (14)	0.0470 (5)
H6A	0.213 (3)	0.3315 (15)	0.594 (2)	0.091 (16)*
H6B	0.222 (3)	0.240 (4)	0.576 (2)	0.104 (18)*
C1	0.58618 (18)	0.50816 (18)	0.54547 (12)	0.0212 (4)
C2	0.51755 (18)	0.40906 (18)	0.49646 (12)	0.0216 (4)
C3	0.43354 (19)	0.40401 (19)	0.45415 (13)	0.0256 (5)
H3	0.3902	0.3424	0.4255	0.031*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Er1	0.01570 (6)	0.01570 (6)	0.02179 (9)	0.00785 (3)	0.000	0.000
O1	0.0218 (8)	0.0214 (8)	0.0293 (8)	0.0121 (7)	−0.0056 (6)	−0.0019 (6)
O2	0.0270 (8)	0.0222 (8)	0.0309 (8)	0.0168 (7)	−0.0069 (7)	−0.0050 (6)
O3	0.0371 (11)	0.0239 (9)	0.0394 (11)	0.0106 (8)	0.0163 (8)	−0.0025 (8)
O4	0.0474 (13)	0.0517 (13)	0.0376 (12)	0.0249 (11)	−0.0043 (10)	0.0091 (10)
O5	0.0335 (11)	0.0505 (13)	0.0505 (14)	0.0202 (10)	0.0094 (10)	0.0035 (11)
O6	0.0434 (13)	0.0436 (14)	0.0534 (14)	0.0212 (11)	0.0057 (10)	0.0082 (11)
C1	0.0202 (10)	0.0208 (10)	0.0221 (10)	0.0099 (9)	0.0003 (8)	0.0004 (8)
C2	0.0215 (10)	0.0217 (10)	0.0226 (10)	0.0115 (9)	0.0011 (8)	0.0015 (8)
C3	0.0259 (11)	0.0216 (11)	0.0318 (12)	0.0137 (10)	−0.0077 (9)	−0.0069 (9)

Geometric parameters (Å, º)

Er1—O1^i	2.4567 (15)	O3—H3B	0.836 (10)
Er1—O1	2.4567 (15)	O4—H4A	0.838 (10)
Er1—O1^ii	2.4567 (15)	O4—H4B	0.842 (10)
Er1—O2^ii	2.3578 (15)	O5—H5A	0.845 (10)
Er1—O2^i	2.3577 (15)	O5—H5B	0.844 (10)
Er1—O2	2.3578 (15)	O6—H6A	0.848 (10)
Er1—O3	2.3636 (18)	O6—H6B	0.843 (10)
Er1—O3^i	2.3636 (18)	C1—C2	1.523 (3)
Er1—O3^ii	2.3637 (18)	C1—C3^iii	1.398 (3)
O1—C1	1.263 (3)	C2—C3	1.381 (3)
O2—C2	1.273 (3)	C3—C1^iii	1.398 (3)
O3—H3A	0.831 (10)	C3—H3	0.9300
O1^i—Er1—O1	119.917 (4)	O3—Er1—O1^ii	139.97 (6)
O1^ii—Er1—O1^i	119.917 (4)	O3—Er1—O1	68.54 (6)
O1^ii—Er1—O1	119.916 (4)	O3^ii—Er1—O1^ii	68.54 (6)
O2^i—Er1—O1^i	65.01 (5)	O3^i—Er1—O1^ii	70.00 (6)
O2^ii—Er1—O1	69.91 (5)	O3^i—Er1—O1^i	68.54 (6)
O2^ii—Er1—O1^ii	65.01 (5)	O3—Er1—O1^i	70.00 (6)
O2—Er1—O1	65.01 (5)	O3^i—Er1—O3^ii	80.60 (8)
O2—Er1—O1^ii	134.93 (5)	O3^i—Er1—O3	80.60 (8)
O2^i—Er1—O1^ii	69.91 (5)	O3—Er1—O3^ii	80.60 (8)
O2^ii—Er1—O1^i	134.93 (5)	C1—O1—Er1	119.88 (14)
O2—Er1—O1^i	69.91 (5)	C2—O2—Er1	123.42 (14)
O2^i—Er1—O1	134.93 (5)	Er1—O3—H3A	118 (2)
O2^i—Er1—O2^ii	78.15 (6)	Er1—O3—H3B	131 (2)
O2^i—Er1—O2	78.15 (6)	H3A—O3—H3B	109 (3)
O2^ii—Er1—O2	78.15 (6)	H4A—O4—H4B	117 (4)
O2^ii—Er1—O3^ii	85.01 (7)	H5A—O5—H5B	112 (5)
O2—Er1—O3^ii	134.96 (6)	H6A—O6—H6B	112 (4)
O2^i—Er1—O3^ii	138.45 (6)	O1—C1—C2	115.38 (19)
O2^i—Er1—O3	134.96 (6)	O1—C1—C3^iii	124.7 (2)
O2—Er1—O3	85.01 (7)	C3^iii—C1—C2	119.92 (19)
O2^ii—Er1—O3	138.45 (6)	O2—C2—C1	114.28 (19)
O2^i—Er1—O3^i	85.01 (7)	O2—C2—C3	125.4 (2)
O2^ii—Er1—O3^i	134.96 (6)	C3—C2—C1	120.26 (19)
O2—Er1—O3^i	138.46 (6)	C1^iii—C3—H3	120.1
O3^ii—Er1—O1^i	139.97 (7)	C2—C3—C1^iii	119.8 (2)
O3^i—Er1—O1	139.97 (6)	C2—C3—H3	120.1
O3^ii—Er1—O1	70.00 (6)
Er1—O1—C1—C2	−8.1 (2)	O2^ii—Er1—O1—C1	96.59 (16)
Er1—O1—C1—C3^iii	172.37 (18)	O2^ii—Er1—O2—C2	−86.3 (2)
Er1—O2—C2—C1	13.9 (3)	O2^i—Er1—O2—C2	−166.47 (17)
Er1—O2—C2—C3	−167.71 (18)	O2—C2—C3—C1^iii	−176.2 (2)
O1^ii—Er1—O1—C1	139.76 (13)	O3^ii—Er1—O1—C1	−171.43 (17)
O1^i—Er1—O1—C1	−34.5 (2)	O3^i—Er1—O1—C1	−126.15 (16)
O1^ii—Er1—O2—C2	−121.30 (16)	O3—Er1—O1—C1	−83.94 (16)
O1—Er1—O2—C2	−13.10 (16)	O3^ii—Er1—O2—C2	−15.9 (2)
O1^i—Er1—O2—C2	126.04 (18)	O3—Er1—O2—C2	55.53 (17)
O1—C1—C2—O2	−3.1 (3)	O3^i—Er1—O2—C2	125.30 (17)
O1—C1—C2—C3	178.4 (2)	C1—C2—C3—C1^iii	2.1 (4)
O2^i—Er1—O1—C1	48.94 (18)	C3^iii—C1—C2—O2	176.4 (2)
O2—Er1—O1—C1	10.65 (15)	C3^iii—C1—C2—C3	−2.1 (4)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3A···O6^iv	0.83 (1)	1.94 (1)	2.769 (3)	174 (3)
O3—H3B···O5^v	0.84 (1)	1.94 (1)	2.758 (3)	165 (3)
O4—H4A···O2^ii	0.84 (1)	1.92 (1)	2.738 (3)	167 (4)
O4—H4B···O4^vi	0.84 (1)	1.98 (1)	2.803 (3)	164 (4)
O5—H5A···O1^i	0.85 (1)	2.09 (3)	2.870 (3)	153 (5)
O5—H5B···O6^vii	0.84 (1)	1.95 (1)	2.794 (3)	174 (5)
O6—H6A···O4^iii	0.85 (1)	1.88 (1)	2.725 (3)	174 (4)
O6—H6B···O5	0.84 (1)	1.91 (1)	2.747 (3)	169 (5)

Symmetry codes: (i) −y+1, x−y, z; (ii) −x+y+1, −x+1, z; (iii) −x+1, −y+1, −z+1; (iv) x−y+2/3, x+1/3, −z+4/3; (v) −x+2/3, −y+1/3, −z+4/3; (vi) x−y+1/3, x−1/3, −z+2/3; (vii) y, −x+y, −z+1.