Tetra­kis(μ-5-bromo­nicotinato)-κ3O,O′:O′;κ3O:O,O′;κ4O:O′-bis­[diaqua­(5-bromo­nicotinato-κ2O,O′)neodymium(III)] dihydrate

Huang, J.; Zhang, J.; Chen, H.-J.

doi:10.1107/S1600536811023798

metal-organic compounds

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Volume 67| Part 7| July 2011| Page m974

doi:10.1107/S1600536811023798

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Tetrakis(μ-5-bromonicotinato)-κ³O,O′:O′;κ³O:O,O′;κ⁴O:O′-bis[diaqua(5-bromonicotinato-κ²O,O′)neodymium(III)] dihydrate

Jing Huang,^a Jin Zhang ^b and Hong-Ji Chen ^b ^*

^aDepartment of Chemistry, Jinan University, Guangzhou 510632, People's Republic of China, and ^bDepartment of Materials Science and Engineering, Jinan University, Guangzhou 510632, People's Republic of China
^*Correspondence e-mail: thjchen@jnu.edu.cn

(Received 2 June 2011; accepted 17 June 2011; online 25 June 2011)

In the title compound, [Nd₂(C₆H₃BrNO₂)₆(H₂O)₄]·2H₂O, the Nd^III ion is coordinated by nine O atoms from one chelating 5-bromonicotinate ligand, four bridging 5-bromonicotinate ligands and two water molecules, exhibiting a distorted three-capped triangular-prismatic geometry. Two Nd^III ions are bridged by four carboxylate groups in bi- and tridentate modes, forming a centrosymmetric dinuclear unit, with an Nd⋯Nd distance of 4.0021 (5) Å, and intramolecular π–π interactions between the pyridine rings [centroid–centroid distance = 3.960 (2) Å]. Intermolecular π–π interactions [centroid–centroid distances = 3.820 (2) and 3.804 (2) Å] and O—H⋯N and O—H⋯O hydrogen bonds connect the dinuclear molecules into a three-dimensional supramolecular network.

Related literature

For general background to lanthanide complexes with carboxylates, see: Ragunathan & Schneider (1996 ); Shibasaki & Yoshikawa (2002 ). For dimeric lanthanide carboxylates, see: Rupam et al. (2010 ); Song et al. (2004 ); Yang & Chen (2009 ).

Experimental

Crystal data

[Nd₂(C₆H₃BrNO₂)₆(H₂O)₄]·2H₂O
M_r = 1602.60
Monoclinic, P 2₁ /n
a = 11.5278 (13) Å
b = 16.6616 (18) Å
c = 12.2711 (13) Å
β = 102.478 (2)°
V = 2301.3 (4) Å³
Z = 2
Mo Kα radiation
μ = 7.52 mm⁻¹
T = 110 K
0.42 × 0.38 × 0.36 mm

Data collection

Bruker APEX CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.059, T_max = 0.067
11552 measured reflections
4999 independent reflections
4295 reflections with I > 2σ(I)
R_int = 0.023

Refinement

R[F² > 2σ(F²)] = 0.022
wR(F²) = 0.054
S = 1.07
4999 reflections
331 parameters
6 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 1.02 e Å⁻³
Δρ_min = −1.07 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O7—H71⋯N3ⁱ	0.84 (1)	1.94 (2)	2.769 (3)	165 (5)
O7—H72⋯O9ⁱⁱ	0.85 (3)	1.97 (2)	2.780 (3)	160 (4)
O8—H81⋯O9ⁱⁱ	0.85 (1)	1.87 (1)	2.699 (3)	164 (3)
O8—H82⋯N2ⁱⁱⁱ	0.85 (1)	1.88 (1)	2.735 (3)	175 (5)
O9—H91⋯N1	0.85 (3)	1.96 (3)	2.801 (3)	172 (4)
O9—H92⋯O4ⁱⁱⁱ	0.84 (1)	2.21 (2)	2.981 (3)	153 (4)
O9—H92⋯O8ⁱⁱⁱ	0.84 (1)	2.37 (4)	2.989 (3)	131 (4)
Symmetry codes: (i) $[-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{5\over 2}}]$ ; (ii) $[x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ ; (iii) $[-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ .

Data collection: SMART (Bruker, 2007 ); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: DIAMOND (Brandenburg, 1999 ); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811023798/hy2440sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811023798/hy2440Isup2.hkl

checkCIF report

Comment top

Part of attentions has been paid to rational design and synthesis of lanthanide carboxylates due to their structural diversity and potential applications as catalysts (Ragunathan & Schneider, 1996; Shibasaki & Yoshikawa, 2002). Recent research results showed that olefin epoxidation reaction can be catalyzed by dimeric lanthanide carboxylates (Rupam et al., 2010). A few crystal structures of dimeric lanthanide carboxylates from 5-bromonicotinic acid (5-BrnicH) ligand, such as [La(5-Brnic)₃(H₂O)₂]₂.H₂O, [Gd(5-Brnic)₃(H₂O)₂]₂ (Rupam et al., 2010) and [Sm(5-Brnic)₃(H₂O)₂]₂.H₂O (Song et al., 2004), have been reported. As the research interest in the catalytic behavior of lanthanide compounds and the easy formation of dinuclear unit by using 5-BrnicH ligand (Yang & Chen, 2009), we synthesized a lanthanide carboxylate, the title compound. We report here its crystal structure.

The title compound is a dimeric lanthanide carboxylate that contains two Nd^III ions, six 5-Brnic ligands and four coordinated and two uncoordinated water molecules (Fig. 1). In the dimer, each Nd^III ion is nine-coordinated by nine O atoms, two of them from one (κ²O,O')-carboxylate group, two from two (κ²O:O')-carboxylate groups, three from two (κ³O,O':O')-carboxylate groups, and two from the coordinated water molecules. The coordination environment of the metal atom can be described as distorted three-capped triangular-prismatic. The two Nd^III ions are bridged by four carboxylate groups in bi- and tridentate modes, forming a centrosymmetric dinuclear unit, with a Nd···Nd distance of 4.0021 (5) Å and intramolecular π–π interactions between the pyridine rings [centroid–centroid distance = 3.960 (2) Å]. Intermolecular π–π interactions [centroid–centroid distances = 3.820 (2) and 3.804 (2) Å] and O—H···N and O—H···O hydrogen bonds (Table 1) connect the dinuclear molecules into a three-dimensional supramolecular network (Fig. 2).

In addition, the nine-coordinated Nd^III ion in the title compound exhibits higher coordination number than that in the dimers [Gd(5-Brnic)₃(H₂O)₂]₂ (Rupam et al., 2010) and [Sm(5-Brnic)₃(H₂O)₂]₂.H₂O (Song et al., 2004). As Nd^III ion has bigger ionic radius than that of Gd^III and Sm^III ions, we owe the increasing in coordination number to the principle of lanthanide contraction.

Related literature top

For general background to lanthanide complexes with carboxylates, see: Ragunathan & Schneider (1996); Shibasaki & Yoshikawa (2002). For dimeric lanthanide carboxylates, see: Rupam et al. (2010); Song et al. (2004); Yang & Chen (2009).

Experimental top

A mixture of neodymium oxide (0.2 mmol, 0.067 g), 5-bromonicotinic acid (0.5 mmol, 0.101 g) and 10 ml water was sealed in a 15 ml Teflon-line autoclave and heated to 363 K for 72 h. The reaction solution was then cooled down to room temperature at a rate of 5 K per hour. Brown single crystals suitable for X-ray crystallography analysis were obtained (yield: 42%). Analysis, calculated for C₁₈H₁₅Br₃N₃NdO₉: C 26.38, H 1.89, N 5.24%; found: C 26.17, H 1.98, N 5.41%. IR (cm^-1, KBr): 3403 bm, 3051 m, 1618 vs, 1550 s, 1541 s, 1442 vs, 1400 vs, 1292 m, 1186 vw, 1130 w, 1026 w, 953 vw, 891 vw, 881 w, 789 m, 741 m, 687 m, 442 m.

Computing details top

Data collection: SMART (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the title compound, showing displacement ellipsoids at the 50% probability level. [Symmetry code: (i) -x, 1-y, 2-z.]
	Fig. 2. Hydrogen-bonded network in the title compound. Dashed lines denote hydrogen bonds.

Tetrakis(µ-5-bromonicotinato)-κ³O,O':O'; κ³O:O,O';κ⁴O:O'-bis[diaqua(5- bromonicotinato-κ²O,O')neodymium(III)] dihydrate top

Crystal data top

[Nd₂(C₆H₃BrNO₂)₆(H₂O)₄]·2H₂O	F(000) = 1524
M_r = 1602.60	D_x = 2.313 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 4999 reflections
a = 11.5278 (13) Å	θ = 2.5–27.1°
b = 16.6616 (18) Å	µ = 7.52 mm⁻¹
c = 12.2711 (13) Å	T = 110 K
β = 102.478 (2)°	Block, brown
V = 2301.3 (4) Å³	0.42 × 0.38 × 0.36 mm
Z = 2

Data collection top

Bruker APEX CCD diffractometer	4999 independent reflections
Radiation source: fine-focus sealed tube	4295 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.023
ϕ and ω scans	θ_max = 27.1°, θ_min = 2.1°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −11→14
T_min = 0.059, T_max = 0.067	k = −21→19
11552 measured reflections	l = −15→15

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)] = 0.022	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.054	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	w = 1/[σ²(F_o²) + (0.0266P)²] where P = (F_o² + 2F_c²)/3
4999 reflections	(Δ/σ)_max = 0.066
331 parameters	Δρ_max = 1.02 e Å⁻³
6 restraints	Δρ_min = −1.07 e Å⁻³

Crystal data top

[Nd₂(C₆H₃BrNO₂)₆(H₂O)₄]·2H₂O	V = 2301.3 (4) Å³
M_r = 1602.60	Z = 2
Monoclinic, P2₁/n	Mo Kα radiation
a = 11.5278 (13) Å	µ = 7.52 mm⁻¹
b = 16.6616 (18) Å	T = 110 K
c = 12.2711 (13) Å	0.42 × 0.38 × 0.36 mm
β = 102.478 (2)°

Data collection top

Bruker APEX CCD diffractometer	4999 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	4295 reflections with I > 2σ(I)
T_min = 0.059, T_max = 0.067	R_int = 0.023
11552 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.022	6 restraints
wR(F²) = 0.054	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	Δρ_max = 1.02 e Å⁻³
4999 reflections	Δρ_min = −1.07 e Å⁻³
331 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Br1	−0.09938 (3)	0.096820 (19)	1.12865 (3)	0.01690 (8)
Br2	0.24543 (3)	0.605255 (19)	0.35014 (3)	0.01538 (8)
Br3	0.08252 (3)	0.38137 (2)	1.62068 (3)	0.01714 (8)
C1	0.0190 (2)	0.35415 (17)	0.9159 (2)	0.0080 (6)
C2	−0.0119 (2)	0.26663 (17)	0.9148 (2)	0.0091 (6)
C3	−0.0484 (3)	0.23220 (18)	1.0047 (2)	0.0100 (6)
H3	−0.0621	0.2641	1.0648	0.012*
C4	−0.0640 (3)	0.15010 (18)	1.0039 (3)	0.0120 (6)
C5	−0.0505 (3)	0.10527 (18)	0.9120 (3)	0.0143 (7)
H5	−0.0654	0.0492	0.9114	0.017*
C6	0.0039 (3)	0.21785 (18)	0.8270 (3)	0.0123 (6)
H6	0.0306	0.2417	0.7665	0.015*
C7	0.2081 (3)	0.60360 (18)	0.7791 (2)	0.0108 (6)
C8	0.2037 (3)	0.64877 (18)	0.6724 (2)	0.0102 (6)
C9	0.2253 (3)	0.60917 (18)	0.5792 (2)	0.0105 (6)
H9	0.2431	0.5535	0.5814	0.013*
C10	0.2200 (3)	0.65385 (18)	0.4825 (2)	0.0103 (6)
C11	0.1923 (3)	0.73465 (18)	0.4816 (3)	0.0134 (6)
H11	0.1892	0.7644	0.4150	0.016*
C12	0.1762 (3)	0.72998 (18)	0.6646 (3)	0.0119 (6)
H12	0.1611	0.7566	0.7286	0.014*
C13	0.1084 (3)	0.42457 (17)	1.1932 (2)	0.0107 (6)
C14	0.1252 (3)	0.37044 (18)	1.2944 (2)	0.0100 (6)
C15	0.0977 (3)	0.39880 (18)	1.3926 (2)	0.0107 (6)
H15	0.0718	0.4525	1.3980	0.013*
C16	0.1090 (3)	0.34655 (19)	1.4820 (2)	0.0110 (6)
C17	0.1423 (3)	0.26774 (18)	1.4697 (2)	0.0130 (6)
H17	0.1485	0.2323	1.5313	0.016*
C18	0.1593 (3)	0.29081 (18)	1.2895 (2)	0.0106 (6)
H18	0.1789	0.2718	1.2228	0.013*
H71	0.313 (4)	0.6236 (10)	1.119 (4)	0.063 (16)*
H72	0.368 (2)	0.548 (2)	1.133 (3)	0.033 (12)*
H81	0.395 (2)	0.4366 (19)	1.0285 (15)	0.010 (9)*
H82	0.340 (4)	0.3837 (7)	0.958 (4)	0.066 (17)*
H91	−0.001 (3)	0.0648 (16)	0.704 (2)	0.026 (11)*
H92	0.0725 (15)	0.017 (3)	0.656 (4)	0.052 (15)*
N1	−0.0172 (2)	0.13855 (15)	0.8243 (2)	0.0146 (6)
N2	0.1699 (2)	0.77251 (15)	0.5710 (2)	0.0126 (5)
N3	0.1659 (2)	0.23932 (15)	1.3751 (2)	0.0142 (6)
Nd1	0.157605 (13)	0.506682 (9)	0.957077 (13)	0.00682 (5)
O1	0.10185 (18)	0.37520 (12)	0.87133 (17)	0.0113 (4)
O2	0.03578 (18)	0.59795 (12)	1.03191 (17)	0.0118 (4)
O3	0.18480 (19)	0.64042 (12)	0.86189 (17)	0.0138 (5)
O4	0.23363 (18)	0.53005 (12)	0.78226 (17)	0.0126 (4)
O5	0.17948 (19)	0.41883 (13)	1.12916 (18)	0.0150 (5)
O6	−0.02224 (19)	0.52807 (13)	0.81744 (17)	0.0144 (5)
O7	0.3080 (2)	0.57471 (14)	1.1001 (2)	0.0164 (5)
O8	0.34606 (19)	0.43444 (13)	0.96599 (18)	0.0116 (4)
O9	0.0016 (2)	0.02805 (14)	0.65696 (19)	0.0140 (5)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.02332 (18)	0.01014 (16)	0.01978 (17)	0.00051 (12)	0.01028 (14)	0.00525 (13)
Br2	0.02280 (17)	0.01451 (17)	0.01077 (15)	−0.00214 (12)	0.00791 (12)	−0.00125 (12)
Br3	0.01782 (16)	0.02518 (19)	0.00977 (15)	−0.00330 (13)	0.00597 (12)	−0.00356 (13)
C1	0.0111 (14)	0.0073 (14)	0.0042 (13)	0.0020 (11)	−0.0014 (11)	0.0000 (11)
C2	0.0093 (14)	0.0054 (14)	0.0124 (15)	0.0008 (11)	0.0015 (12)	0.0000 (12)
C3	0.0099 (14)	0.0086 (15)	0.0124 (15)	0.0018 (11)	0.0047 (12)	−0.0013 (12)
C4	0.0102 (15)	0.0105 (15)	0.0159 (16)	0.0010 (11)	0.0043 (12)	0.0040 (13)
C5	0.0166 (16)	0.0051 (15)	0.0207 (17)	−0.0013 (12)	0.0033 (13)	−0.0007 (13)
C6	0.0120 (15)	0.0119 (16)	0.0129 (15)	−0.0012 (12)	0.0023 (12)	−0.0013 (12)
C7	0.0089 (14)	0.0108 (15)	0.0129 (15)	−0.0020 (11)	0.0029 (12)	0.0026 (12)
C8	0.0113 (15)	0.0081 (15)	0.0109 (15)	−0.0023 (11)	0.0015 (12)	0.0016 (12)
C9	0.0102 (14)	0.0101 (15)	0.0116 (15)	−0.0011 (11)	0.0029 (12)	−0.0011 (12)
C10	0.0117 (15)	0.0107 (15)	0.0080 (14)	−0.0032 (11)	0.0011 (12)	−0.0016 (12)
C11	0.0171 (16)	0.0118 (16)	0.0115 (15)	−0.0028 (12)	0.0038 (12)	0.0029 (12)
C12	0.0116 (15)	0.0119 (16)	0.0123 (15)	−0.0017 (12)	0.0031 (12)	−0.0011 (12)
C13	0.0150 (15)	0.0062 (15)	0.0092 (15)	−0.0059 (12)	−0.0012 (12)	0.0008 (12)
C14	0.0089 (14)	0.0089 (15)	0.0116 (15)	−0.0013 (11)	0.0011 (12)	0.0017 (12)
C15	0.0122 (15)	0.0073 (15)	0.0125 (15)	0.0002 (11)	0.0027 (12)	−0.0008 (12)
C16	0.0109 (15)	0.0143 (16)	0.0085 (14)	−0.0028 (12)	0.0035 (12)	−0.0013 (12)
C17	0.0169 (16)	0.0126 (16)	0.0091 (15)	0.0001 (12)	0.0018 (12)	0.0060 (12)
C18	0.0137 (15)	0.0111 (16)	0.0069 (14)	−0.0003 (11)	0.0019 (12)	−0.0006 (12)
N1	0.0177 (14)	0.0087 (13)	0.0179 (14)	−0.0015 (10)	0.0051 (11)	−0.0043 (11)
N2	0.0169 (13)	0.0088 (13)	0.0122 (13)	−0.0023 (10)	0.0030 (11)	0.0025 (10)
N3	0.0193 (14)	0.0095 (13)	0.0137 (14)	0.0029 (10)	0.0034 (11)	0.0044 (11)
Nd1	0.01072 (8)	0.00413 (8)	0.00615 (8)	0.00027 (6)	0.00303 (6)	0.00031 (6)
O1	0.0151 (11)	0.0077 (11)	0.0124 (11)	−0.0005 (8)	0.0059 (9)	0.0002 (8)
O2	0.0175 (11)	0.0081 (11)	0.0105 (10)	0.0025 (9)	0.0046 (9)	0.0008 (9)
O3	0.0235 (12)	0.0086 (11)	0.0110 (11)	−0.0032 (9)	0.0074 (9)	−0.0013 (9)
O4	0.0197 (11)	0.0083 (11)	0.0113 (11)	0.0020 (9)	0.0064 (9)	0.0023 (9)
O5	0.0155 (11)	0.0180 (12)	0.0112 (11)	−0.0039 (9)	0.0020 (9)	0.0056 (9)
O6	0.0198 (12)	0.0088 (11)	0.0120 (11)	0.0027 (9)	−0.0026 (9)	−0.0002 (9)
O7	0.0201 (13)	0.0080 (12)	0.0187 (12)	0.0007 (9)	−0.0009 (10)	−0.0038 (10)
O8	0.0137 (11)	0.0078 (12)	0.0124 (11)	0.0004 (9)	0.0009 (9)	−0.0017 (9)
O9	0.0157 (12)	0.0138 (12)	0.0128 (12)	0.0015 (9)	0.0039 (10)	−0.0042 (9)

Geometric parameters (Å, º) top

Br1—C4	1.888 (3)	C13—O5	1.255 (4)
Br2—C10	1.894 (3)	C13—C14	1.513 (4)
Br3—C16	1.884 (3)	C14—C18	1.389 (4)
C1—O1	1.249 (3)	C14—C15	1.393 (4)
C1—O2ⁱ	1.273 (3)	C15—C16	1.385 (4)
C1—C2	1.500 (4)	C15—H15	0.9500
C2—C3	1.386 (4)	C16—C17	1.385 (4)
C2—C6	1.393 (4)	C17—N3	1.335 (4)
C3—C4	1.380 (4)	C17—H17	0.9500
C3—H3	0.9500	C18—N3	1.345 (4)
C4—C5	1.389 (4)	C18—H18	0.9500
C5—N1	1.340 (4)	Nd1—O2	2.384 (2)
C5—H5	0.9500	Nd1—O6	2.414 (2)
C6—N1	1.342 (4)	Nd1—O1	2.455 (2)
C6—H6	0.9500	Nd1—O7	2.461 (2)
C7—O4	1.259 (3)	Nd1—O8	2.465 (2)
C7—O3	1.264 (4)	Nd1—O4	2.517 (2)
C7—C8	1.501 (4)	Nd1—O5	2.537 (2)
C8—C9	1.389 (4)	Nd1—O3	2.566 (2)
C8—C12	1.388 (4)	Nd1—O2ⁱ	2.856 (2)
C9—C10	1.390 (4)	Nd1—Nd1ⁱ	4.0022 (5)
C9—H9	0.9500	O7—H71	0.84 (1)
C10—C11	1.383 (4)	O7—H72	0.85 (3)
C11—N2	1.338 (4)	O8—H81	0.85 (1)
C11—H11	0.9500	O8—H82	0.85 (1)
C12—N2	1.338 (4)	O9—H91	0.85 (3)
C12—H12	0.9500	O9—H92	0.84 (1)
C13—O6ⁱ	1.253 (4)

O1—C1—O2ⁱ	123.6 (3)	O7—Nd1—O8	73.44 (7)
O1—C1—C2	118.1 (3)	O2—Nd1—O4	124.90 (7)
O2ⁱ—C1—C2	118.1 (3)	O6—Nd1—O4	77.05 (7)
O1—C1—Nd1	53.38 (14)	O1—Nd1—O4	83.10 (7)
O2ⁱ—C1—Nd1	71.76 (16)	O7—Nd1—O4	102.44 (8)
C2—C1—Nd1	161.08 (19)	O8—Nd1—O4	69.36 (7)
C3—C2—C6	119.1 (3)	O2—Nd1—O5	90.48 (7)
C3—C2—C1	120.5 (3)	O6—Nd1—O5	126.28 (7)
C6—C2—C1	120.2 (3)	O1—Nd1—O5	79.14 (7)
C4—C3—C2	117.8 (3)	O7—Nd1—O5	75.17 (7)
C4—C3—H3	121.1	O8—Nd1—O5	75.71 (7)
C2—C3—H3	121.1	O4—Nd1—O5	143.95 (7)
C3—C4—C5	120.1 (3)	O2—Nd1—O3	76.21 (7)
C3—C4—Br1	120.8 (2)	O6—Nd1—O3	73.70 (7)
C5—C4—Br1	119.1 (2)	O1—Nd1—O3	128.77 (7)
N1—C5—C4	122.2 (3)	O7—Nd1—O3	77.78 (7)
N1—C5—H5	118.9	O8—Nd1—O3	104.54 (7)
C4—C5—H5	118.9	O4—Nd1—O3	51.57 (7)
N1—C6—C2	122.7 (3)	O5—Nd1—O3	151.64 (7)
N1—C6—H6	118.7	O2—Nd1—O2ⁱ	80.82 (7)
C2—C6—H6	118.7	O6—Nd1—O2ⁱ	64.17 (7)
O4—C7—O3	122.4 (3)	O1—Nd1—O2ⁱ	48.76 (6)
O4—C7—C8	118.6 (3)	O7—Nd1—O2ⁱ	133.17 (7)
O3—C7—C8	119.0 (3)	O8—Nd1—O2ⁱ	112.90 (7)
O4—C7—Nd1	60.93 (15)	O4—Nd1—O2ⁱ	123.63 (6)
O3—C7—Nd1	63.19 (15)	O5—Nd1—O2ⁱ	63.04 (6)
C8—C7—Nd1	165.9 (2)	O3—Nd1—O2ⁱ	136.46 (6)
C9—C8—C12	119.0 (3)	O2—Nd1—C7	99.62 (8)
C9—C8—C7	120.1 (3)	O6—Nd1—C7	70.22 (8)
C12—C8—C7	120.9 (3)	O1—Nd1—C7	104.64 (8)
C8—C9—C10	117.7 (3)	O7—Nd1—C7	93.22 (8)
C8—C9—H9	121.1	O8—Nd1—C7	89.25 (8)
C10—C9—H9	121.1	O4—Nd1—C7	25.93 (7)
C11—C10—C9	119.7 (3)	O5—Nd1—C7	163.03 (8)
C11—C10—Br2	119.1 (2)	O3—Nd1—C7	26.09 (7)
C9—C10—Br2	121.1 (2)	O2ⁱ—Nd1—C7	131.83 (7)
N2—C11—C10	122.5 (3)	O2—Nd1—C1	105.66 (8)
N2—C11—H11	118.8	O6—Nd1—C1	70.10 (7)
C10—C11—H11	118.8	O1—Nd1—C1	24.09 (7)
N2—C12—C8	123.0 (3)	O7—Nd1—C1	141.37 (8)
N2—C12—H12	118.5	O8—Nd1—C1	91.49 (7)
C8—C12—H12	118.5	O4—Nd1—C1	105.05 (7)
O6ⁱ—C13—O5	126.3 (3)	O5—Nd1—C1	66.61 (7)
O6ⁱ—C13—C14	114.8 (3)	O3—Nd1—C1	140.85 (7)
O5—C13—C14	118.9 (3)	O2ⁱ—Nd1—C1	25.04 (7)
C18—C14—C15	118.7 (3)	C7—Nd1—C1	122.56 (8)
C18—C14—C13	121.4 (3)	O2—Nd1—Nd1ⁱ	44.79 (5)
C15—C14—C13	119.7 (3)	O6—Nd1—Nd1ⁱ	60.37 (5)
C16—C15—C14	118.2 (3)	O1—Nd1—Nd1ⁱ	83.95 (5)
C16—C15—H15	120.9	O7—Nd1—Nd1ⁱ	112.19 (6)
C14—C15—H15	120.9	O8—Nd1—Nd1ⁱ	143.38 (5)
C17—C16—C15	119.4 (3)	O4—Nd1—Nd1ⁱ	137.40 (5)
C17—C16—Br3	119.5 (2)	O5—Nd1—Nd1ⁱ	71.42 (5)
C15—C16—Br3	121.1 (2)	O3—Nd1—Nd1ⁱ	112.04 (5)
N3—C17—C16	123.0 (3)	O2ⁱ—Nd1—Nd1ⁱ	36.03 (4)
N3—C17—H17	118.5	C7—Nd1—Nd1ⁱ	125.13 (6)
C16—C17—H17	118.5	C1—Nd1—Nd1ⁱ	60.94 (6)
N3—C18—C14	123.0 (3)	C1—O1—Nd1	102.53 (17)
N3—C18—H18	118.5	C1ⁱ—O2—Nd1	172.35 (19)
C14—C18—H18	118.5	C1ⁱ—O2—Nd1ⁱ	83.20 (17)
C5—N1—C6	118.0 (3)	Nd1—O2—Nd1ⁱ	99.18 (7)
C12—N2—C11	118.0 (3)	C7—O3—Nd1	90.72 (17)
C17—N3—C18	117.7 (3)	C7—O4—Nd1	93.14 (17)
O2—Nd1—O6	72.07 (7)	C13—O5—Nd1	121.09 (19)
O2—Nd1—O1	127.79 (7)	C13ⁱ—O6—Nd1	135.0 (2)
O6—Nd1—O1	73.88 (7)	Nd1—O7—H71	129 (3)
O2—Nd1—O7	79.30 (8)	Nd1—O7—H72	118 (3)
O6—Nd1—O7	143.42 (7)	H71—O7—H72	113 (4)
O1—Nd1—O7	142.70 (7)	Nd1—O8—H81	115 (2)
O2—Nd1—O8	151.76 (7)	Nd1—O8—H82	115 (3)
O6—Nd1—O8	135.81 (7)	H81—O8—H82	100 (4)
O1—Nd1—O8	74.33 (7)	H91—O9—H92	110 (4)

Symmetry code: (i) −x, −y+1, −z+2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O7—H71···N3ⁱⁱ	0.84 (1)	1.94 (2)	2.769 (3)	165 (5)
O7—H72···O9ⁱⁱⁱ	0.85 (3)	1.97 (2)	2.780 (3)	160 (4)
O8—H81···O9ⁱⁱⁱ	0.85 (1)	1.87 (1)	2.699 (3)	164 (3)
O8—H82···N2^iv	0.85 (1)	1.88 (1)	2.735 (3)	175 (5)
O9—H91···N1	0.85 (3)	1.96 (3)	2.801 (3)	172 (4)
O9—H92···O4^iv	0.84 (1)	2.21 (2)	2.981 (3)	153 (4)
O9—H92···O8^iv	0.84 (1)	2.37 (4)	2.989 (3)	131 (4)

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

Experimental details

Crystal data
Chemical formula	[Nd₂(C₆H₃BrNO₂)₆(H₂O)₄]·2H₂O
M_r	1602.60
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	110
a, b, c (Å)	11.5278 (13), 16.6616 (18), 12.2711 (13)
β (°)	102.478 (2)
V (Å³)	2301.3 (4)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	7.52
Crystal size (mm)	0.42 × 0.38 × 0.36

Data collection
Diffractometer	Bruker APEX CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.059, 0.067
No. of measured, independent and observed [I > 2σ(I)] reflections	11552, 4999, 4295
R_int	0.023
(sin θ/λ)_max (Å⁻¹)	0.641

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.022, 0.054, 1.07
No. of reflections	4999
No. of parameters	331
No. of restraints	6
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	1.02, −1.07

Computer programs: SMART (Bruker, 2007), SAINT (Bruker, 2007), SHELXTL (Sheldrick, 2008), DIAMOND (Brandenburg, 1999).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O7—H71···N3ⁱ	0.84 (1)	1.94 (2)	2.769 (3)	165 (5)
O7—H72···O9ⁱⁱ	0.85 (3)	1.97 (2)	2.780 (3)	160 (4)
O8—H81···O9ⁱⁱ	0.85 (1)	1.87 (1)	2.699 (3)	164 (3)
O8—H82···N2ⁱⁱⁱ	0.85 (1)	1.88 (1)	2.735 (3)	175 (5)
O9—H91···N1	0.85 (3)	1.96 (3)	2.801 (3)	172 (4)
O9—H92···O4ⁱⁱⁱ	0.84 (1)	2.21 (2)	2.981 (3)	153 (4)
O9—H92···O8ⁱⁱⁱ	0.84 (1)	2.37 (4)	2.989 (3)	131 (4)

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

References

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