Poly[bis­(μ-2-amino-4-nitro­benzoato)di-μ-aqua-dirubidium]

Smith, G.

doi:10.1107/S1600536814008861

metal-organic compounds

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ISSN: 2056-9890

Volume 70| Part 5| May 2014| Pages m192-m193

doi:10.1107/S1600536814008861

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Poly[bis(μ-2-amino-4-nitrobenzoato)di-μ-aqua-dirubidium]

Graham Smith ^a ^*

^aScience and Engineering Faculty, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4001, Australia
^*Correspondence e-mail: g.smith@qut.edu.au

(Received 2 April 2014; accepted 18 April 2014; online 30 April 2014)

In the structure of the title salt, [Rb₂(C₇H₅N₂O₄)₂(H₂O)₂]_n, the asymmetric unit comprises two independent and different seven-coordinate Rb⁺ cations, one forming an RbO₇ polyhedron, the other a RbO₆N polyhedron, each of which is considerably distorted. The RbO₇ polyhedron comprises bridging O-atom donors from two water molecules, three carboxylate groups, and two nitro groups. The RbO₆N polyhedron comprises the two bridging water molecules, one monodentate amine N-atom donor, one carboxyl O-atom donor and three O-atom donors from nitro groups (one from the chelate bridge). The extension of the dinuclear unit gives a three-dimensional polymeric structure which is stabilized by both intra- and intermolecular amine N—H⋯O and water O—H⋯O hydrogen bonds to carboxyl and water O-atom acceptors, as well as a number of inter-ring π–π interactions [minimum centroid–centroid separation = 3.364 (2) Å]. The title salt is isostructural with the analogous caesium salt.

CCDC reference: 998206

Related literature

For the structures of some rubidium salts of substituted benzoic acids, see: Wiesbrock & Schmidbaur (2003 ); Dinnebier et al. (2002 ); Hu et al. (2005 ); Miao et al. (2011 ). For the structures of caesium 4-nitroanthranilate and caesium 3,5-dinitrosalicylate, see: Smith & Wermuth (2011 ) and Meng (2011 ), respectively. For the structures of the sodium and potassium 4-nitroanthranilates, see: Smith (2013 ).

Experimental

Crystal data

[Rb₂(C₇H₅N₂O₄)₂(H₂O)₂]
M_r = 569.23
Monoclinic, P 2₁ /n
a = 15.2938 (9) Å
b = 6.8601 (3) Å
c = 17.8075 (10) Å
β = 99.996 (5)°
V = 1839.95 (17) Å³
Z = 4
Mo Kα radiation
μ = 5.39 mm⁻¹
T = 200 K
0.30 × 0.18 × 0.08 mm

Data collection

Oxford Diffraction Gemini-S CCD diffractometer
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2013 ) T_min = 0.691, T_max = 0.980
6954 measured reflections
3634 independent reflections
2708 reflections with I > 2σ(I)
R_int = 0.046

Refinement

R[F² > 2σ(F²)] = 0.046
wR(F²) = 0.075
S = 1.03
3634 reflections
295 parameters
8 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.61 e Å⁻³
Δρ_min = −0.51 e Å⁻³

Table 1
Selected bond lengths (Å)

Rb1—O1W	3.041 (3)
Rb1—O2W	3.006 (3)
Rb1—O42A	3.064 (3)
Rb1—O42Aⁱ	3.092 (3)
Rb1—O12Aⁱⁱ	3.074 (3)
Rb1—O11Bⁱⁱⁱ	3.059 (3)
Rb1—O12A^iv	2.998 (3)
Rb2—O1W	2.994 (3)
Rb2—O2W	2.897 (3)
Rb2—O41A	2.992 (3)
Rb2—N2B	3.177 (4)
Rb2—O42B^v	2.984 (3)
Rb2—O12B^vi	2.947 (3)
Rb2—O42B^iv	3.069 (3)
Symmetry codes: (i) $[-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ ; (ii) -x+1, -y, -z+1; (iii) -x+2, -y, -z+1; (iv) $[x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ ; (v) $[-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (vi) -x+2, -y+1, -z+1.

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2A—H21A⋯O12A	0.91 (2)	1.97 (3)	2.686 (5)	134 (3)
N2A—H21A⋯O1W^vii	0.91 (2)	2.58 (4)	3.149 (5)	122 (3)
N2A—H22A⋯O11B^v	0.94 (3)	2.46 (3)	3.206 (5)	136 (3)
N2B—H21B⋯O11A^viii	0.90 (3)	2.01 (3)	2.831 (5)	151 (3)
N2B—H22B⋯O12B	0.90 (3)	1.88 (3)	2.644 (6)	142 (4)
O1W—H11W⋯O11B^vi	0.88 (3)	1.92 (4)	2.783 (4)	167 (4)
O1W—H12W⋯O12A^viii	0.89 (3)	1.96 (4)	2.847 (4)	176 (2)
O2W—H21W⋯O11Aⁱⁱ	0.89 (4)	1.93 (4)	2.823 (4)	178 (7)
O2W—H22W⋯O12Bⁱⁱⁱ	0.88 (4)	1.95 (5)	2.812 (5)	166 (5)
Symmetry codes: (ii) -x+1, -y, -z+1; (iii) -x+2, -y, -z+1; (v) $[-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (vi) -x+2, -y+1, -z+1; (vii) $[x-{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ ; (viii) -x+1, -y+1, -z+1.

Data collection: CrysAlis PRO (Agilent, 2013); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) within WinGX (Farrugia, 2012 ); molecular graphics: PLATON (Spek, 2009 ); software used to prepare material for publication: PLATON.

Supporting information

CCDC reference: 998206

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536814008861/wm5020sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536814008861/wm5020Isup2.hkl

checkCIF report

Comment top

The structures of alkali metal salts derived from aromatic carboxylic acids are of interest (Smith, 2013), particularly with the heavier metals Rb and Cs, because of the expanded metals' coordination spheres and their ability to form coordination polymers. With 4-nitroanthranilic acid (4-NAA), a three-dimensional coordination polymeric structure [Cs₂(C₇H₅N₂O₄)₂(H₂O)₂] was described (Smith & Wermuth, 2011) and from the reaction of rubidium carbonate with 4-NAA, orange-red crystals of the title compound [Rb₂(C₇H₅N₂O₄)₂(H₂O)₂], were obtained, the structure of which is reported herein.

The Rb salt has the same formula as the Cs salt and has similar crystal data [comparative 200 K unit cell data for the Cs complex: a = 15.3615 (3), b = 6.9573 (2), c = 18.3714 (4) Å, β = 97.903 (2)°, V = 1944.79 (8) Å³, Z = 4, space group P2₁/n]. The X-ray analysis reported here confirms that the Rb and Cs analogues are isotypic.

In the structure of the Rb salt, the dinuclear asymmetric unit contains two independent and different seven-coordinate Rb⁺ cations, with both having irregular coordination environments (Fig. 1). The RbO₇ polyhedron about Rb1 comprises bridging oxygen donors from two water molecules, three carboxylate groups, and a nitro group, with one O atom doubly bridging [Rb—O range 2.998 (3)–3.092 (3) Å]. The RbO₆N polyhedron about Rb2 comprises the two bridging water atoms, one monodentate amine N donor, one carboxyl O donor and three O donors from nitro groups (one doubly bridging) [Rb—O range 2.897 (3)–3.069 (3) Å] (Table 1). The Rb1···Rb2 separation in this dinuclear unit is 4.1208 (7) Å. Extension of this unit gives an overall three-dimensional polymeric structure (Fig. 2) which is stabilized by both intra- and intermolecular amine N—H···O and water O—H···O hydrogen bonds to both carboxyl and water O-atom acceptors (Table 2). Also, there are several inter-ring π···π interactions involving both ring 1 (C1A–C6A) and ring 2 (C1B–C6B) with a minimum ring centroid separation 1···1^viii of 3.364 (2) Å and a maximum ring centroid separation: 2···2^ix of 3.556 (2) Å [for symmetry code (viii), see Table 1; for symmetry code (ix) -x + 3/2, y + 1/2, -z + 1/2].

The minor difference between the two isotypic Rb and Cs salt structures is that in the description of the Cs salt, the coordination about Cs1 includes two longer Cs—O bonds to O41B^iv [3.326 (2) Å] (see Fig. 1) and to O1W1ⁱ [3.414 (3) Å]. In the title Rb salt, the equivalent values [3.342 (3) and 3.495 (3) Å] preclude these as Rb—O bonds.

These structural features, including expanded metal coordination spheres and multiple bridging with polymeric extensions, are similar to those found in other Rb salts with substituted benzoic acids, e.g. rubidium 3,5-dinitrobenzoate (8-coordinate) (Miao et al., 2011), rubidium anthranilate (7-coordinate) (Wiesbrock & Schmidbaur, 2003), rubidium salicylate (8-coordinate) (Dinnebier et al., 2002) and rubidium 3,5-dinitosalicylate (10-coordinate) (Meng, 2011), this last Rb complex being isotypic with its Cs analogue (Hu et al., 2005).

Related literature top

For the structures of some rubidium salts of substituted benzoic acids, see: Wiesbrock & Schmidbaur (2003); Dinnebier et al. (2002); Hu et al. (2005); Miao et al. (2011). For the structures of caesium 4-nitroanthranilate and caesium 3,5-dinitrosalicylate, see: Smith & Wermuth (2011) and Meng (2011), respectively. For the structures of the sodium and potassium 4-nitroanthranilates, see: Smith (2013).

Experimental top

The title compound was synthesized by heating together for 5 minutes, 0.1 mmol of rubidium carbonate and 0.2 mmol of 4-nitroanthranilic acid in 10 ml of 1:8 (v/v) ethanol–water. Partial room temperature evaporation of the solution gave orange-red flat prisms of the title complex from which a suitable specimen was cleaved for the X-ray analysis.

Computing details top

Data collection: CrysAlis PRO (Agilent, 2013); cell refinement: CrysAlis PRO (Agilent, 2013); data reduction: CrysAlis PRO (Agilent, 2013); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) within WinGX (Farrugia, 2012); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular configuration and atom-numbering scheme for the dinuclear repeat unit of the title complex, with non-H atoms drawn as 30% probability displacement ellipsoids. Intramolecular hydrogen bonds are shown as dashed lines. For symmetry codes, see Table 1.
	Fig. 2. The polymeric structure in the unit cell viewed down b. Non-associative H atoms are omitted and hydrogen bonds are shown as dashed lines.

Poly[bis(µ-2-amino-4-nitrobenzoato)di-µ-aqua-dirubidium] top

Crystal data top

[Rb₂(C₇H₅N₂O₄)₂(H₂O)₂]	F(000) = 1120
M_r = 569.23	D_x = 2.055 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 1131 reflections
a = 15.2938 (9) Å	θ = 3.4–26.4°
b = 6.8601 (3) Å	µ = 5.39 mm⁻¹
c = 17.8075 (10) Å	T = 200 K
β = 99.996 (5)°	Plate, orange red
V = 1839.95 (17) Å³	0.30 × 0.18 × 0.08 mm
Z = 4

Data collection top

Oxford Diffraction Gemini-S CCD diffractometer	3634 independent reflections
Radiation source: Enhance (Mo) X-ray source	2708 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.046
Detector resolution: 16.077 pixels mm^-1	θ_max = 26.0°, θ_min = 3.3°
ω scans	h = −15→18
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2013)	k = −7→8
T_min = 0.691, T_max = 0.980	l = −15→21
6954 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.075	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ²(F_o²) + (0.0163P)²] where P = (F_o² + 2F_c²)/3
3634 reflections	(Δ/σ)_max = 0.001
295 parameters	Δρ_max = 0.61 e Å⁻³
8 restraints	Δρ_min = −0.51 e Å⁻³

Crystal data top

[Rb₂(C₇H₅N₂O₄)₂(H₂O)₂]	V = 1839.95 (17) Å³
M_r = 569.23	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 15.2938 (9) Å	µ = 5.39 mm⁻¹
b = 6.8601 (3) Å	T = 200 K
c = 17.8075 (10) Å	0.30 × 0.18 × 0.08 mm
β = 99.996 (5)°

Data collection top

Oxford Diffraction Gemini-S CCD diffractometer	3634 independent reflections
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2013)	2708 reflections with I > 2σ(I)
T_min = 0.691, T_max = 0.980	R_int = 0.046
6954 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.046	8 restraints
wR(F²) = 0.075	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	Δρ_max = 0.61 e Å⁻³
3634 reflections	Δρ_min = −0.51 e Å⁻³
295 parameters

Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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

	x	y	z	U_iso*/U_eq
Rb1	0.84018 (3)	−0.11232 (6)	0.71945 (2)	0.0291 (2)
Rb2	0.90021 (3)	0.21443 (7)	0.54097 (3)	0.0333 (2)
O1W	0.8411 (2)	0.3229 (4)	0.68713 (19)	0.0313 (11)
O2W	0.8861 (2)	−0.2009 (5)	0.5656 (2)	0.0395 (12)
O11A	0.26528 (19)	0.4400 (4)	0.47291 (17)	0.0316 (11)
O11B	1.01609 (19)	0.4261 (4)	0.26964 (17)	0.0324 (11)
O12A	0.29906 (19)	0.4056 (4)	0.35752 (16)	0.0312 (11)
O12B	0.9810 (2)	0.4779 (5)	0.38434 (17)	0.0349 (11)
O41A	0.7146 (2)	0.0750 (5)	0.5397 (2)	0.0404 (11)
O41B	0.5388 (2)	0.4326 (5)	0.20204 (19)	0.0459 (13)
O42A	0.6701 (2)	0.1017 (5)	0.64817 (19)	0.0394 (12)
O42B	0.5826 (2)	0.4724 (5)	0.09497 (19)	0.0463 (14)
N2A	0.4616 (3)	0.2771 (6)	0.3444 (2)	0.0345 (14)
N2B	0.8117 (3)	0.4663 (6)	0.3981 (2)	0.0350 (14)
N4A	0.6588 (2)	0.1193 (5)	0.5785 (2)	0.0293 (14)
N4B	0.5972 (2)	0.4538 (5)	0.1643 (2)	0.0295 (12)
C1A	0.4092 (3)	0.3222 (6)	0.4651 (2)	0.0174 (12)
C1B	0.8639 (3)	0.4516 (6)	0.2769 (2)	0.0198 (12)
C2A	0.4746 (3)	0.2689 (6)	0.4225 (2)	0.0219 (12)
C2B	0.7949 (3)	0.4594 (6)	0.3196 (2)	0.0232 (14)
C3A	0.5580 (3)	0.2062 (6)	0.4619 (2)	0.0234 (14)
C3B	0.7072 (3)	0.4573 (6)	0.2809 (2)	0.0233 (14)
C4A	0.5716 (3)	0.1917 (6)	0.5395 (2)	0.0206 (14)
C4B	0.6909 (3)	0.4514 (6)	0.2033 (2)	0.0212 (14)
C5A	0.5086 (3)	0.2394 (6)	0.5834 (3)	0.0233 (14)
C5B	0.7571 (3)	0.4458 (6)	0.1594 (2)	0.0240 (14)
C6A	0.4284 (3)	0.3055 (6)	0.5442 (2)	0.0206 (12)
C6B	0.8427 (3)	0.4444 (6)	0.1980 (2)	0.0235 (14)
C11A	0.3177 (3)	0.3931 (6)	0.4292 (3)	0.0213 (14)
C11B	0.9617 (3)	0.4523 (6)	0.3130 (3)	0.0252 (16)
H3A	0.60430	0.17440	0.43460	0.0280*
H5A	0.51990	0.22740	0.63740	0.0280*
H3B	0.65930	0.45980	0.30860	0.0280*
H5B	0.74390	0.44300	0.10520	0.0290*
H6A	0.38380	0.34160	0.57260	0.0250*
H6B	0.88960	0.43830	0.16940	0.0280*
H11W	0.882 (2)	0.414 (5)	0.695 (3)	0.0470*
H12W	0.796 (2)	0.404 (5)	0.671 (3)	0.0470*
H21A	0.4027 (14)	0.282 (6)	0.325 (2)	0.0420*
H21B	0.771 (2)	0.503 (6)	0.426 (2)	0.0420*
H21W	0.839 (2)	−0.278 (6)	0.553 (3)	0.0590*
H22A	0.500 (2)	0.195 (5)	0.323 (2)	0.0420*
H22B	0.8686 (15)	0.503 (6)	0.412 (3)	0.0420*
H22W	0.927 (3)	−0.292 (6)	0.573 (3)	0.0590*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Rb1	0.0343 (3)	0.0294 (3)	0.0220 (2)	0.0052 (2)	0.0004 (2)	−0.0010 (2)
Rb2	0.0369 (3)	0.0340 (3)	0.0255 (3)	−0.0029 (2)	−0.0039 (2)	−0.0018 (2)
O1W	0.0256 (18)	0.0285 (19)	0.036 (2)	−0.0001 (15)	−0.0055 (15)	0.0014 (16)
O2W	0.032 (2)	0.039 (2)	0.044 (2)	0.0029 (17)	−0.0035 (17)	0.0010 (19)
O11A	0.0209 (17)	0.050 (2)	0.0235 (18)	0.0042 (16)	0.0029 (14)	−0.0060 (16)
O11B	0.0211 (17)	0.042 (2)	0.033 (2)	−0.0003 (16)	0.0017 (14)	−0.0054 (17)
O12A	0.0328 (18)	0.045 (2)	0.0138 (17)	0.0093 (16)	−0.0012 (13)	0.0057 (15)
O12B	0.0358 (19)	0.045 (2)	0.0197 (18)	0.0043 (17)	−0.0065 (14)	−0.0050 (16)
O41A	0.0231 (18)	0.043 (2)	0.054 (2)	0.0041 (17)	0.0035 (17)	−0.0052 (19)
O41B	0.0234 (18)	0.074 (3)	0.042 (2)	−0.0015 (19)	0.0106 (16)	0.003 (2)
O42A	0.038 (2)	0.041 (2)	0.033 (2)	0.0045 (18)	−0.0113 (16)	0.0062 (17)
O42B	0.0323 (19)	0.075 (3)	0.029 (2)	−0.0023 (19)	−0.0023 (16)	0.0082 (19)
N2A	0.033 (2)	0.045 (3)	0.026 (2)	0.006 (2)	0.0067 (19)	−0.005 (2)
N2B	0.033 (2)	0.051 (3)	0.022 (2)	0.006 (2)	0.0075 (19)	0.000 (2)
N4A	0.025 (2)	0.018 (2)	0.042 (3)	−0.0049 (19)	−0.0024 (19)	0.001 (2)
N4B	0.028 (2)	0.031 (2)	0.029 (2)	−0.001 (2)	0.0032 (18)	−0.0013 (19)
C1A	0.023 (2)	0.013 (2)	0.016 (2)	−0.0031 (19)	0.0027 (18)	0.0016 (18)
C1B	0.023 (2)	0.015 (2)	0.021 (2)	0.003 (2)	0.0029 (19)	−0.0017 (19)
C2A	0.026 (2)	0.021 (2)	0.018 (2)	−0.003 (2)	0.0017 (19)	−0.001 (2)
C2B	0.034 (3)	0.015 (2)	0.020 (2)	0.003 (2)	0.003 (2)	0.0008 (19)
C3A	0.021 (2)	0.019 (2)	0.031 (3)	−0.003 (2)	0.007 (2)	−0.005 (2)
C3B	0.023 (2)	0.021 (2)	0.028 (3)	0.000 (2)	0.010 (2)	−0.001 (2)
C4A	0.017 (2)	0.014 (2)	0.028 (3)	−0.002 (2)	−0.0042 (19)	−0.001 (2)
C4B	0.020 (2)	0.014 (2)	0.028 (3)	−0.003 (2)	0.000 (2)	0.003 (2)
C5A	0.026 (2)	0.021 (3)	0.021 (2)	0.000 (2)	−0.0015 (19)	−0.001 (2)
C5B	0.028 (2)	0.025 (3)	0.018 (2)	−0.003 (2)	0.0014 (19)	−0.001 (2)
C6A	0.024 (2)	0.017 (2)	0.020 (2)	−0.003 (2)	0.0020 (19)	−0.0019 (19)
C6B	0.025 (2)	0.021 (2)	0.026 (3)	−0.004 (2)	0.009 (2)	−0.002 (2)
C11A	0.019 (2)	0.018 (2)	0.026 (3)	−0.002 (2)	0.0015 (19)	0.001 (2)
C11B	0.029 (3)	0.018 (2)	0.028 (3)	0.003 (2)	0.003 (2)	−0.001 (2)

Geometric parameters (Å, º) top

Rb1—O1W	3.041 (3)	N2B—C2B	1.378 (5)
Rb1—O2W	3.006 (3)	N4A—C4A	1.479 (5)
Rb1—O42A	3.064 (3)	N4B—C4B	1.480 (5)
Rb1—O42Aⁱ	3.092 (3)	N2A—H21A	0.91 (2)
Rb1—O12Aⁱⁱ	3.074 (3)	N2A—H22A	0.94 (3)
Rb1—O11Bⁱⁱⁱ	3.059 (3)	N2B—H21B	0.90 (3)
Rb1—O12A^iv	2.998 (3)	N2B—H22B	0.90 (3)
Rb2—O1W	2.994 (3)	C1A—C2A	1.405 (6)
Rb2—O2W	2.897 (3)	C1A—C6A	1.393 (5)
Rb2—O41A	2.992 (3)	C1A—C11A	1.514 (6)
Rb2—N2B	3.177 (4)	C1B—C2B	1.405 (6)
Rb2—O42B^v	2.984 (3)	C1B—C6B	1.387 (5)
Rb2—O12B^vi	2.947 (3)	C1B—C11B	1.522 (7)
Rb2—O42B^iv	3.069 (3)	C2A—C3A	1.412 (6)
O11A—C11A	1.253 (6)	C2B—C3B	1.398 (6)
O11B—C11B	1.242 (6)	C3A—C4A	1.365 (5)
O12A—C11A	1.262 (6)	C3B—C4B	1.362 (5)
O12B—C11B	1.266 (6)	C4A—C5A	1.381 (6)
O41A—N4A	1.226 (5)	C4B—C5B	1.383 (6)
O41B—N4B	1.216 (5)	C5A—C6A	1.378 (6)
O42A—N4A	1.229 (5)	C5B—C6B	1.369 (6)
O42B—N4B	1.223 (5)	C3A—H3A	0.9500
O1W—H11W	0.88 (3)	C3B—H3B	0.9500
O1W—H12W	0.89 (3)	C5A—H5A	0.9500
O2W—H21W	0.89 (4)	C5B—H5B	0.9500
O2W—H22W	0.88 (4)	C6A—H6A	0.9500
N2A—C2A	1.372 (5)	C6B—H6B	0.9500

O1W—Rb1—O2W	90.95 (9)	Rb1—O2W—H22W	106 (3)
O1W—Rb1—O42A	58.84 (9)	H21W—O2W—H22W	98 (4)
O1W—Rb1—O42Aⁱ	140.33 (9)	Rb2—O2W—H22W	131 (3)
O1W—Rb1—O12Aⁱⁱ	125.72 (8)	Rb2—O2W—H21W	129 (3)
O1W—Rb1—O11Bⁱⁱⁱ	132.54 (8)	Rb2—N2B—C2B	140.6 (3)
O1W—Rb1—O12A^iv	72.50 (8)	O41A—N4A—C4A	118.6 (3)
O2W—Rb1—O42A	92.01 (9)	O41A—N4A—O42A	123.7 (3)
O2W—Rb1—O42Aⁱ	128.13 (9)	O42A—N4A—C4A	117.7 (3)
O2W—Rb1—O12Aⁱⁱ	73.42 (8)	O41B—N4B—O42B	123.2 (3)
O2W—Rb1—O11Bⁱⁱⁱ	68.69 (9)	O41B—N4B—C4B	118.9 (3)
O2W—Rb1—O12A^iv	163.43 (9)	O42B—N4B—C4B	117.9 (3)
O42A—Rb1—O42Aⁱ	117.91 (9)	C2A—N2A—H22A	113 (2)
O12Aⁱⁱ—Rb1—O42A	69.90 (8)	H21A—N2A—H22A	121 (3)
O11Bⁱⁱⁱ—Rb1—O42A	155.88 (8)	C2A—N2A—H21A	110 (2)
O12A^iv—Rb1—O42A	80.17 (8)	Rb2—N2B—H22B	71 (3)
O12Aⁱⁱ—Rb1—O42Aⁱ	78.56 (8)	C2B—N2B—H21B	123 (2)
O11Bⁱⁱⁱ—Rb1—O42Aⁱ	68.66 (8)	Rb2—N2B—H21B	87 (2)
O12A^iv—Rb1—O42Aⁱ	68.24 (8)	H21B—N2B—H22B	120 (4)
O11Bⁱⁱⁱ—Rb1—O12Aⁱⁱ	90.13 (8)	C2B—N2B—H22B	107 (3)
O12Aⁱⁱ—Rb1—O12A^iv	116.59 (8)	C6A—C1A—C11A	118.1 (4)
O11Bⁱⁱⁱ—Rb1—O12A^iv	122.11 (8)	C2A—C1A—C11A	123.2 (3)
O1W—Rb2—O2W	94.08 (9)	C2A—C1A—C6A	118.7 (4)
O1W—Rb2—O41A	69.92 (9)	C2B—C1B—C6B	119.0 (4)
O1W—Rb2—N2B	114.21 (10)	C2B—C1B—C11B	123.1 (3)
O1W—Rb2—O42B^v	157.81 (9)	C6B—C1B—C11B	117.9 (4)
O1W—Rb2—O12B^vi	71.65 (8)	N2A—C2A—C1A	123.1 (4)
O1W—Rb2—O42B^iv	103.10 (9)	C1A—C2A—C3A	118.5 (3)
O2W—Rb2—O41A	65.87 (9)	N2A—C2A—C3A	118.4 (4)
O2W—Rb2—N2B	128.58 (10)	N2B—C2B—C3B	119.7 (4)
O2W—Rb2—O42B^v	66.11 (10)	N2B—C2B—C1B	121.7 (4)
O2W—Rb2—O12B^vi	133.82 (9)	C1B—C2B—C3B	118.7 (3)
O2W—Rb2—O42B^iv	68.24 (9)	C2A—C3A—C4A	119.4 (4)
O41A—Rb2—N2B	84.03 (11)	C2B—C3B—C4B	119.5 (4)
O41A—Rb2—O42B^v	91.89 (9)	C3A—C4A—C4A	123.9 (4)
O12B^vi—Rb2—O41A	137.91 (9)	N4A—C4A—C5A	118.3 (3)
O41A—Rb2—O42B^iv	132.73 (9)	N4A—C4A—C3A	117.8 (4)
O42B^v—Rb2—N2B	74.83 (10)	C3B—C4B—C5B	123.5 (4)
O12B^vi—Rb2—N2B	96.63 (10)	N4B—C4B—C5B	118.6 (3)
O42B^iv—Rb2—N2B	135.71 (10)	N4B—C4B—C3B	117.9 (4)
O12B^vi—Rb2—O42B^v	129.07 (9)	C4A—C5A—C6A	116.0 (4)
O42B^v—Rb2—O42B^iv	79.55 (9)	C4B—C5B—C6B	116.5 (3)
O12B^vi—Rb2—O42B^iv	72.67 (9)	C1A—C6A—C5A	123.5 (4)
Rb1—O1W—Rb2	86.13 (8)	C1B—C6B—C5B	122.9 (4)
Rb1—O2W—Rb2	88.54 (9)	O12A—C11A—C1A	118.6 (4)
Rb1ⁱⁱⁱ—O11B—C11B	127.9 (3)	O11A—C11A—O12A	123.7 (4)
Rb1ⁱⁱ—O12A—C11A	115.1 (3)	O11A—C11A—C1A	117.7 (4)
Rb1^vii—O12A—C11A	145.0 (3)	O11B—C11B—O12B	125.4 (4)
Rb1ⁱⁱ—O12A—Rb1^vii	99.88 (8)	O11B—C11B—C1B	116.9 (4)
Rb2^vi—O12B—C11B	124.8 (3)	O12B—C11B—C1B	117.7 (4)
Rb2—O41A—N4A	132.0 (3)	C2A—C3A—H3A	120.00
Rb1—O42A—N4A	115.2 (2)	C4A—C3A—H3A	120.00
Rb1—O42A—Rb1^viii	98.05 (9)	C2B—C3B—H3B	120.00
Rb1^viii—O42A—N4A	133.7 (3)	C4B—C3B—H3B	120.00
Rb2^ix—O42B—N4B	148.3 (3)	C4A—C5A—H5A	122.00
Rb2^vii—O42B—N4B	105.6 (2)	C6A—C5A—H5A	122.00
Rb2^ix—O42B—Rb2^vii	100.45 (10)	C4B—C5B—H5B	122.00
Rb1—O1W—H12W	130 (2)	C6B—C5B—H5B	122.00
Rb2—O1W—H11W	90 (3)	C1A—C6A—H6A	118.00
Rb2—O1W—H12W	102 (3)	C5A—C6A—H6A	118.00
H11W—O1W—H12W	96 (3)	C1B—C6B—H6B	119.00
Rb1—O1W—H11W	134 (2)	C5B—C6B—H6B	118.00
Rb1—O2W—H21W	93 (3)

O2W—Rb1—O1W—Rb2	−4.05 (8)	O1W—Rb2—O12B^vi—C11B^vi	30.1 (3)
O42A—Rb1—O1W—Rb2	−95.84 (10)	O2W—Rb2—O12B^vi—C11B^vi	−47.5 (4)
O42Aⁱ—Rb1—O1W—Rb2	166.82 (10)	O41A—Rb2—O12B^vi—C11B^vi	55.0 (4)
O12Aⁱⁱ—Rb1—O1W—Rb2	−74.20 (10)	N2B—Rb2—O12B^vi—C11B^vi	143.4 (3)
O11Bⁱⁱⁱ—Rb1—O1W—Rb2	57.38 (13)	O1W—Rb2—O42B^iv—Rb2ⁱⁱⁱ	157.48 (9)
O12A^iv—Rb1—O1W—Rb2	175.23 (10)	O1W—Rb2—O42B^iv—N4B^iv	−4.3 (3)
O1W—Rb1—O2W—Rb2	4.18 (9)	O2W—Rb2—O42B^iv—Rb2ⁱⁱⁱ	68.29 (10)
O42A—Rb1—O2W—Rb2	63.04 (9)	O2W—Rb2—O42B^iv—N4B^iv	−93.5 (3)
O42Aⁱ—Rb1—O2W—Rb2	−168.43 (8)	O41A—Rb2—O42B^iv—Rb2ⁱⁱⁱ	82.84 (14)
O12Aⁱⁱ—Rb1—O2W—Rb2	131.36 (9)	O41A—Rb2—O42B^iv—N4B^iv	−79.0 (3)
O11Bⁱⁱⁱ—Rb1—O2W—Rb2	−131.82 (10)	N2B—Rb2—O42B^iv—Rb2ⁱⁱⁱ	−55.24 (16)
O1W—Rb1—O42A—N4A	85.4 (3)	N2B—Rb2—O42B^iv—N4B^iv	142.9 (2)
O1W—Rb1—O42A—Rb1^viii	−61.55 (10)	Rb1ⁱⁱⁱ—O11B—C11B—O12B	55.8 (6)
O2W—Rb1—O42A—N4A	−4.5 (3)	Rb1ⁱⁱⁱ—O11B—C11B—C1B	−123.6 (3)
O2W—Rb1—O42A—Rb1^viii	−151.44 (9)	Rb1ⁱⁱ—O12A—C11A—O11A	−69.9 (5)
O42Aⁱ—Rb1—O42A—N4A	−140.4 (3)	Rb1ⁱⁱ—O12A—C11A—C1A	111.6 (3)
O42Aⁱ—Rb1—O42A—Rb1^viii	72.69 (11)	Rb1^vii—O12A—C11A—O11A	112.4 (5)
O12Aⁱⁱ—Rb1—O42A—N4A	−76.1 (3)	Rb1^vii—O12A—C11A—C1A	−66.1 (6)
O12Aⁱⁱ—Rb1—O42A—Rb1^viii	137.04 (10)	Rb2^vi—O12B—C11B—O11B	56.1 (5)
O11Bⁱⁱⁱ—Rb1—O42A—N4A	−40.3 (4)	Rb2^vi—O12B—C11B—C1B	−124.4 (3)
O11Bⁱⁱⁱ—Rb1—O42A—Rb1^viii	172.79 (15)	Rb2—O41A—N4A—O42A	−59.4 (5)
O12A^iv—Rb1—O42A—N4A	160.8 (3)	Rb2—O41A—N4A—C4A	122.8 (3)
O12A^iv—Rb1—O42A—Rb1^viii	13.87 (8)	Rb1—O42A—N4A—O41A	−7.6 (5)
O1W—Rb1—O42Aⁱ—Rb1ⁱ	119.97 (12)	Rb1—O42A—N4A—C4A	170.2 (3)
O1W—Rb1—O42Aⁱ—N4Aⁱ	−16.9 (4)	Rb1^viii—O42A—N4A—O41A	124.0 (4)
O2W—Rb1—O42Aⁱ—Rb1ⁱ	−71.66 (12)	Rb1^viii—O42A—N4A—C4A	−58.2 (5)
O2W—Rb1—O42Aⁱ—N4Aⁱ	151.4 (3)	Rb2^ix—O42B—N4B—O41B	120.8 (5)
O42A—Rb1—O42Aⁱ—Rb1ⁱ	46.14 (12)	Rb2^ix—O42B—N4B—C4B	−61.0 (6)
O42A—Rb1—O42Aⁱ—N4Aⁱ	−90.8 (3)	Rb2^vii—O42B—N4B—O41B	−23.4 (4)
O1W—Rb1—O12Aⁱⁱ—Rb1ⁱ	−131.30 (9)	Rb2^vii—O42B—N4B—C4B	154.7 (3)
O1W—Rb1—O12Aⁱⁱ—C11Aⁱⁱ	47.4 (3)	Rb2—N2B—C2B—C1B	−62.6 (6)
O2W—Rb1—O12Aⁱⁱ—Rb1ⁱ	149.82 (10)	Rb2—N2B—C2B—C3B	116.5 (5)
O2W—Rb1—O12Aⁱⁱ—C11Aⁱⁱ	−31.5 (3)	O41A—N4A—C4A—C3A	−0.3 (6)
O42A—Rb1—O12Aⁱⁱ—Rb1ⁱ	−111.67 (10)	O41A—N4A—C4A—C5A	179.3 (4)
O42A—Rb1—O12Aⁱⁱ—C11Aⁱⁱ	67.0 (3)	O42A—N4A—C4A—C3A	−178.2 (4)
O1W—Rb1—O11Bⁱⁱⁱ—C11Bⁱⁱⁱ	−44.3 (4)	O42A—N4A—C4A—C5A	1.4 (6)
O2W—Rb1—O11Bⁱⁱⁱ—C11Bⁱⁱⁱ	26.2 (3)	O41B—N4B—C4B—C3B	−10.5 (6)
O42A—Rb1—O11Bⁱⁱⁱ—C11Bⁱⁱⁱ	65.0 (4)	O41B—N4B—C4B—C5B	170.3 (4)
O1W—Rb1—O12A^iv—Rb1^viii	46.25 (8)	O42B—N4B—C4B—C3B	171.3 (4)
O1W—Rb1—O12A^iv—C11A^iv	−131.6 (5)	O42B—N4B—C4B—C5B	−7.9 (6)
O42A—Rb1—O12A^iv—Rb1^viii	−14.02 (8)	C6A—C1A—C2A—N2A	178.9 (4)
O42A—Rb1—O12A^iv—C11A^iv	168.1 (5)	C6A—C1A—C2A—C3A	−1.9 (6)
O2W—Rb2—O1W—Rb1	4.22 (9)	C11A—C1A—C2A—N2A	0.3 (7)
O41A—Rb2—O1W—Rb1	66.67 (9)	C11A—C1A—C2A—C3A	179.5 (4)
N2B—Rb2—O1W—Rb1	140.07 (10)	C2A—C1A—C6A—C5A	0.1 (6)
O42B^v—Rb2—O1W—Rb1	30.1 (3)	C11A—C1A—C6A—C5A	178.8 (4)
O12B^vi—Rb2—O1W—Rb1	−130.83 (10)	C2A—C1A—C11A—O11A	−178.7 (4)
O42B^iv—Rb2—O1W—Rb1	−64.38 (9)	C2A—C1A—C11A—O12A	−0.2 (6)
O1W—Rb2—O2W—Rb1	−4.26 (9)	C6A—C1A—C11A—O11A	2.7 (6)
O41A—Rb2—O2W—Rb1	−70.11 (9)	C6A—C1A—C11A—O12A	−178.8 (4)
N2B—Rb2—O2W—Rb1	−129.90 (12)	C6B—C1B—C2B—N2B	179.8 (4)
O42B^v—Rb2—O2W—Rb1	−173.89 (11)	C6B—C1B—C2B—C3B	0.7 (6)
O12B^vi—Rb2—O2W—Rb1	64.09 (13)	C11B—C1B—C2B—N2B	−0.7 (6)
O42B^iv—Rb2—O2W—Rb1	98.23 (10)	C11B—C1B—C2B—C3B	−179.8 (4)
O1W—Rb2—O41A—N4A	17.2 (3)	C2B—C1B—C6B—C5B	0.4 (6)
O2W—Rb2—O41A—N4A	121.5 (4)	C11B—C1B—C6B—C5B	−179.1 (4)
N2B—Rb2—O41A—N4A	−101.3 (4)	C2B—C1B—C11B—O11B	173.3 (4)
O42B^v—Rb2—O41A—N4A	−175.8 (4)	C2B—C1B—C11B—O12B	−6.2 (6)
O12B^vi—Rb2—O41A—N4A	−8.0 (4)	C6B—C1B—C11B—O11B	−7.2 (6)
O42B^iv—Rb2—O41A—N4A	106.7 (4)	C6B—C1B—C11B—O12B	173.3 (4)
O1W—Rb2—N2B—C2B	−159.6 (5)	N2A—C2A—C3A—C4A	−178.2 (4)
O2W—Rb2—N2B—C2B	−42.3 (5)	C1A—C2A—C3A—C4A	2.6 (6)
O41A—Rb2—N2B—C2B	−94.7 (5)	N2B—C2B—C3B—C4B	179.7 (4)
O42B^v—Rb2—N2B—C2B	−1.1 (5)	C1B—C2B—C3B—C4B	−1.2 (6)
O12B^vi—Rb2—N2B—C2B	127.6 (5)	C2A—C3A—C4A—N4A	178.0 (4)
O42B^iv—Rb2—N2B—C2B	55.7 (5)	C2A—C3A—C4A—C5A	−1.6 (7)
O1W—Rb2—O42B^v—N4B^v	115.8 (5)	C2B—C3B—C4B—N4B	−178.7 (4)
O1W—Rb2—O42B^v—Rb2ⁱⁱⁱ	−99.1 (2)	C2B—C3B—C4B—C5B	0.5 (6)
O2W—Rb2—O42B^v—N4B^v	144.2 (5)	N4A—C4A—C5A—C6A	−179.8 (4)
O2W—Rb2—O42B^v—Rb2ⁱⁱⁱ	−70.70 (10)	C3A—C4A—C5A—C6A	−0.2 (6)
O41A—Rb2—O42B^v—N4B^v	81.7 (5)	N4B—C4B—C5B—C6B	179.8 (4)
O41A—Rb2—O42B^v—Rb2ⁱⁱⁱ	−133.17 (10)	C3B—C4B—C5B—C6B	0.7 (6)
N2B—Rb2—O42B^v—N4B^v	−1.6 (5)	C4A—C5A—C6A—C1A	1.0 (6)
N2B—Rb2—O42B^v—Rb2ⁱⁱⁱ	143.53 (12)	C4B—C5B—C6B—C1B	−1.1 (6)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2A—H21A···O12A	0.91 (2)	1.97 (3)	2.686 (5)	134 (3)
N2A—H21A···O1W^vii	0.91 (2)	2.58 (4)	3.149 (5)	122 (3)
N2A—H22A···O11B^v	0.94 (3)	2.46 (3)	3.206 (5)	136 (3)
N2B—H21B···O11A^x	0.90 (3)	2.01 (3)	2.831 (5)	151 (3)
N2B—H22B···O12B	0.90 (3)	1.88 (3)	2.644 (6)	142 (4)
O1W—H11W···O11B^vi	0.88 (3)	1.92 (4)	2.783 (4)	167 (4)
O1W—H12W···O12A^x	0.89 (3)	1.96 (4)	2.847 (4)	176 (2)
O2W—H21W···O11Aⁱⁱ	0.89 (4)	1.93 (4)	2.823 (4)	178 (7)
O2W—H22W···O12Bⁱⁱⁱ	0.88 (4)	1.95 (5)	2.812 (5)	166 (5)
C5A—H5A···O11B^xi	0.95	2.59	3.488 (6)	158
C6A—H6A···O11A	0.95	2.40	2.755 (5)	101
C6B—H6B···O11B	0.95	2.40	2.739 (5)	101

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

Selected bond lengths (Å) top

Rb1—O1W	3.041 (3)	Rb2—O1W	2.994 (3)
Rb1—O2W	3.006 (3)	Rb2—O2W	2.897 (3)
Rb1—O42A	3.064 (3)	Rb2—O41A	2.992 (3)
Rb1—O42Aⁱ	3.092 (3)	Rb2—N2B	3.177 (4)
Rb1—O12Aⁱⁱ	3.074 (3)	Rb2—O42B^v	2.984 (3)
Rb1—O11Bⁱⁱⁱ	3.059 (3)	Rb2—O12B^vi	2.947 (3)
Rb1—O12A^iv	2.998 (3)	Rb2—O42B^iv	3.069 (3)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2A—H21A···O12A	0.91 (2)	1.97 (3)	2.686 (5)	134 (3)
N2A—H21A···O1W^vii	0.91 (2)	2.58 (4)	3.149 (5)	122 (3)
N2A—H22A···O11B^v	0.94 (3)	2.46 (3)	3.206 (5)	136 (3)
N2B—H21B···O11A^viii	0.90 (3)	2.01 (3)	2.831 (5)	151 (3)
N2B—H22B···O12B	0.90 (3)	1.88 (3)	2.644 (6)	142 (4)
O1W—H11W···O11B^vi	0.88 (3)	1.92 (4)	2.783 (4)	167 (4)
O1W—H12W···O12A^viii	0.89 (3)	1.96 (4)	2.847 (4)	176 (2)
O2W—H21W···O11Aⁱⁱ	0.89 (4)	1.93 (4)	2.823 (4)	178 (7)
O2W—H22W···O12Bⁱⁱⁱ	0.88 (4)	1.95 (5)	2.812 (5)	166 (5)

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

Acknowledgements

The author acknowledges financial support from the Science and Engineering Faculty and the University Library, Queensland University of Technology.

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