[Sm(NO₃)₃(TPTZ)(H₂O)]·2H₂O [TPTZ is 2,4,6-tris(2-pyridyl)-1,3,5-triazine]

The title compound, aqua­tris­(nitrato)[2,4,6-tris(2-pyridyl)-1,3,5-triazine]samarium dihydrate, [Sm(NO₃)₃­(C₁₈H₁₂N₆)­(H₂O)]·­2H₂O, was prepared from Sm(NO₃)₃·6H₂O and 2,4,6-tris(2-pyridyl)-1,3,5-triazine. The metal atom is ten-coordinate being bonded to the terdentate TPTZ ligand, three bidentate nitrates and a water mol­ecule.

S1. Comment

There is much current interest in the use of tridentate ligands such as 2,4,6-tri-2-pyridyl-1,3,5-triazine (TPTZ) and terpyridine and its derivatives for the extraction and separation of metal ions (Chan et al., 1996; Byers et al., 1996). These ligands are being used in the nuclear industry as solvent extraction reagents since they are able to separate trivalent actinides An^III over lanthanides Ln^III from nitric acid media in synergistic combination with a weak acid such as 2-bromodecanoic acid. The ligands have been found to form 1:1 complexes with lanthanides in the presence of nitric acid in which they act as an approximately planar tridentate ligands (Chan et al., 1996) and this is likely to be the mode in which they separate the metal ions.

The inclusion of 2-bromopropionic acid in the complex preparation was an effort to better replicate the conditions under which the liquid-liquid extraction experiments take place as it closely resembles the most often used synergist, 2-bromodecanoic acid. In the liquid-liquid extraction process, the ligand and synergist in hydrogenated tetrapropene are used to extract the metal ions from nitric acid media. We have previously shown that a mixture of 2-bromodecanoic acid, samarium nitrate and terpyridine (terpy) can result in the protonation of terpyridine and the formation of an ion-pair of formula [(H₂terpy)(NO₃)]⁺ [Sm(terpy)(NO₃)₄]^- in which the diprotonated terpy is not coordinated to the Sm^III ion (Drew, Hudson, Iveson, Russell, Liljenzin et al., 1998).

The extraction performance of terpyridine has indeed been found to decrease at higher nitric acid concentrations because it becomes diprotonated, cannot coordinate to the metal and also has increased solubility in the aqueous phase (Hågstrom et al., 1999). However in the presence of 2-bromopropionic acid, none of the heterocyclic nitrogen atoms in TPTZ were protonated, a fact which presumably reflects the lower basicity of the TPTZ nitrogen atoms compared to those in terpyridine.

The structure of the title compound, (I), is shown in Figure 1 and is the first to be determined of a lanthanide(III) nitrate/TPTZ complex. The metal atom is ten-coordinate, being bonded to three nitrogen atoms from the TPTZ ligand, three nitrate anions and one water molecule. In addition there are two water molecules in the asymmetric unit. The bond to the water molecule is by far the shortest at 2.420 (4) Å compared to 2.492 (4)–2.615 (4) Å for the Sm—O(nitrate) bonds. The Sm—N51 bond to the central nitrogen atom of the ligand is at 2.571 (4) Å significantly shorter than the other two bonds from the metal to the ligand, viz 2.644 (5) and 2.631 (4) Å. \sch

The angle subtended by the pyridine rings at the central triazine ring is 6.3 (2), 4.9 (2)° for the coordinated rings and 17.5 (2)° for the uncoordinated rings. The metal atom is 0.05 Å from the plane of the central triazine ring.

The structure of the TPTZ ligand has been published previously (Drew, Hudson, Iveson, Russell & Madic, 1998). Other high coordinate related structures containing this ligand include [Ce(TPTZ(NO₃)₄] (Chan et al., 1996) in which the metal is 11-co-ordinate, the metal being bound to the terdentate TPTZ and four bidentate nitrates, [Eu(TPTZ)Cl₃(HOMe)₂] (Wietzke et al., 1999) in which the metal is eight-co-ordinate being bonded to the terdentate ligand, three chlorides and two solvent methanols, and [Pr(TPTZ)(OAc)₃]₂, a centrosymmetric dimer in which the metal is ten-coordinate being bonded to the terdentate ligand, and three acetates, one of which bridges to the other metal (Wietzke et al., 1999).

The M—N bond lengths in the present structure are, as expected, shorter than the Ce—N and Pr—N distances (2.720, 2.673, 2.733; 2.674, 2.687, 2.717 Å and comparable with the Eu—N distances 2.646, 2.555, 2.646 Å in the above TPTZ structures.

It is noteworthy that in TPTZ metal complexes the unbonded pyridine nitrogen atoms form hydrogen bonds with solvent molecules. Thus in the above Eu and Pr structures, solvent methanol forms a bifurcated hydrogen bond to N82 and N55 (using the numbering scheme in the present structure) while in the present structure the water molecule O(300) forms a single hydrogen bond to N82 at 2.801 (6) Å.

There is an extensive hydrogen-bond pattern in the crystal involving the three water molecules. Hydrogen bonds are O(100)···O(200)(-x,-y,-z) 2.676 (6), O(100)···O(21) (1 - x, 1 - y, 1 - z) 2.838 (5), O(300)···O(200) 2.791 (7), O(300)···O(200) 2.791 (7), and O(300)···O(33)(-x, 1 - y, -z) 2.944 (6) Å.

S2. Experimental

The title compound was prepared by initially adding Sm(NO₃)₃·6H₂O (0.0711 g, 0.16 mmol) in CH₃CN (10 cm³) dropwise to a stirred solution containing TPTZ (0.05 g, 16 mmol) in CH₃CN (10 cm³). After stirring for a few minutes, 2-bromopropionic acid (0.024 g, 0.16 mmol) was added and the solution was stirred for a further 30 min. It did not prove necessary to separate out the acid and suitable crystals were obtained after three weeks at room temperature.

S3. Refinement

87.1% of the unique data were collected up to θ of 25.97°. This relatively low value is due to the fact that the data were collected on an image plate system where higher coverages are often difficult to obtain for triclinic systems.

The structure of (I) was refined with no unusual features. Non-hydrogen atoms were refined with anisotropic displacement parameters and hydrogen atoms bonded to carbon atoms were introduced in calculated positions. Hydrogen atoms bonded to the bonded water molecules were located from a difference Fourier map but those on the free water molecules were not located and not included. All hydrogen atoms were refined with displacement parameters fixed at values of 1.2 times that of the atom to which they were bonded.

Computing details

Data collection: XDS (Kabsch, 1991); cell refinement: XDS; data reduction: XDS; program(s) used to solve structure: SHELXS86 (Sheldrick, 1990); program(s) used to refine structure: SHELXL93 (Sheldrick, 1993); molecular graphics: PLATON (Spek,1994).

Figures

Fig. 1. The structure of the title compound. Ellipsoids are scaled for 25% probability. Hydrogen atoms are included with small arbitrary radii.

(I)

Crystal data

[Sm(NO3)3(C18H12N6)(H2O)]·2H2O	Z = 2
Mr = 702.76	F(000) = 694
Triclinic, P1	Dx = 1.866 Mg m^−3
a = 9.592 (12) Å	Mo Kα radiation, λ = 0.71073 Å
b = 11.989 (14) Å	Cell parameters from 4276 reflections
c = 12.574 (14) Å	θ = 2.0–26.0°
α = 115.219 (10)°	µ = 2.43 mm^−1
β = 102.68 (1)°	T = 293 K
γ = 94.734 (10)°	Needle, colourless
V = 1251 (3) Å^3	0.30 × 0.10 × 0.10 mm

Data collection

Marresearch Image Plate diffractometer	4275 independent reflections
Radiation source: fine-focus sealed tube	4052 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.000
95 frames at 2° intervals, counting time 2 min. scans	θmax = 26.0°, θmin = 3.2°
Absorption correction: empirical (using intensity measurements) DIFABS (Walker & Stuart, 1983)	h = 0→11
Tmin = 0.473, Tmax = 0.784	k = −14→14
4275 measured reflections	l = −15→14

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: see text
R[F^2 > 2σ(F^2)] = 0.033	See text
wR(F^2) = 0.094	Calculated w = 1/[σ^2(Fo^2) + (0.0526P)^2 + 1.8862P] where P = (Fo^2 + 2Fc^2)/3
S = 1.09	(Δ/σ)max = 0.001
4275 reflections	Δρmax = 0.92 e Å^−3
380 parameters	Δρmin = −0.96 e Å^−3
3 restraints	Extinction correction: SHELXL93 (Sheldrick, 1993), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: none

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
Sm	0.26660 (2)	0.341971 (17)	0.238013 (16)	0.02055 (10)
O11	0.2244 (4)	0.1123 (3)	0.1788 (4)	0.0497 (10)
N12	0.0877 (5)	0.0903 (4)	0.1548 (3)	0.0313 (9)
O13	0.0301 (4)	0.1826 (4)	0.1646 (4)	0.0409 (9)
O14	0.0166 (6)	−0.0122 (4)	0.1245 (4)	0.0558 (12)
O21	0.3043 (4)	0.5373 (3)	0.4331 (3)	0.0357 (8)
N22	0.2169 (5)	0.4944 (4)	0.4779 (3)	0.0335 (9)
O23	0.1516 (4)	0.3822 (4)	0.4118 (3)	0.0436 (9)
O24	0.1984 (5)	0.5616 (5)	0.5752 (4)	0.0587 (12)
O31	0.3350 (4)	0.5199 (4)	0.1934 (4)	0.0425 (9)
O34	0.5164 (4)	0.4947 (4)	0.3089 (4)	0.0412 (9)
N32	0.4680 (5)	0.5547 (4)	0.2546 (4)	0.0358 (9)
O33	0.5434 (5)	0.6451 (4)	0.2567 (5)	0.0663 (14)
O100	0.4424 (4)	0.2997 (4)	0.3794 (3)	0.0392 (9)
H11	0.522 (4)	0.348 (4)	0.429 (5)	0.047*
H12	0.431 (6)	0.232 (3)	0.384 (5)	0.047*
N51	0.1686 (4)	0.2754 (3)	0.0079 (3)	0.0217 (7)
C52	0.2427 (5)	0.2169 (4)	−0.0729 (4)	0.0245 (9)
N53	0.1970 (4)	0.1838 (4)	−0.1920 (3)	0.0295 (8)
C54	0.0703 (5)	0.2107 (4)	−0.2305 (4)	0.0259 (9)
N55	−0.0124 (4)	0.2686 (4)	−0.1578 (3)	0.0263 (8)
C56	0.0433 (4)	0.3005 (4)	−0.0395 (4)	0.0213 (8)
C61	−0.0379 (4)	0.3723 (4)	0.0463 (4)	0.0218 (8)
N62	0.0264 (4)	0.4157 (3)	0.1669 (3)	0.0245 (7)
C63	−0.0458 (6)	0.4808 (5)	0.2448 (4)	0.0323 (10)
H63	−0.0033	0.5107	0.3283	0.039*
C64	−0.1812 (5)	0.5059 (4)	0.2067 (4)	0.0328 (10)
H64	−0.2278	0.5515	0.2640	0.039*
C65	−0.2455 (5)	0.4635 (5)	0.0852 (5)	0.0356 (10)
H65	−0.3367	0.4789	0.0581	0.043*
C66	−0.1716 (5)	0.3963 (5)	0.0018 (4)	0.0311 (10)
H66	−0.2112	0.3683	−0.0818	0.037*
C71	0.3860 (5)	0.1924 (4)	−0.0252 (4)	0.0259 (9)
N72	0.4334 (4)	0.2362 (4)	0.0982 (4)	0.0300 (8)
C73	0.5653 (5)	0.2191 (5)	0.1437 (5)	0.0377 (11)
H73	0.6009	0.2491	0.2279	0.045*
C74	0.6509 (6)	0.1581 (6)	0.0695 (6)	0.0426 (12)
H74	0.7422	0.1489	0.1049	0.051*
C75	0.6030 (6)	0.1119 (6)	−0.0535 (6)	0.0448 (13)
H75	0.6589	0.0694	−0.1036	0.054*
C76	0.4664 (6)	0.1304 (5)	−0.1028 (5)	0.0392 (12)
H76	0.4302	0.1011	−0.1869	0.047*
C81	0.0191 (6)	0.1813 (4)	−0.3619 (4)	0.0287 (10)
N82	−0.1200 (5)	0.1849 (5)	−0.4060 (4)	0.0398 (10)
C83	−0.1640 (8)	0.1658 (7)	−0.5223 (5)	0.0513 (15)
H83	−0.2599	0.1690	−0.5539	0.062*
C84	−0.0729 (8)	0.1416 (6)	−0.5968 (5)	0.0503 (15)
H84	−0.1075	0.1281	−0.6773	0.060*
C85	0.0674 (7)	0.1376 (5)	−0.5520 (5)	0.0458 (13)
H85	0.1304	0.1215	−0.6011	0.055*
C86	0.1156 (6)	0.1578 (5)	−0.4325 (4)	0.0370 (11)
H86	0.2116	0.1556	−0.3998	0.044*
O300	−0.3719 (5)	0.1569 (4)	−0.3342 (4)	0.0536 (10)
O200	−0.4386 (7)	−0.1045 (5)	−0.4304 (5)	0.0800 (18)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Sm	0.02075 (14)	0.02083 (14)	0.01938 (13)	0.00350 (9)	0.00507 (9)	0.00896 (9)
O11	0.040 (2)	0.0314 (19)	0.069 (3)	0.0069 (17)	0.0099 (19)	0.0176 (18)
N12	0.042 (2)	0.0262 (19)	0.0203 (17)	−0.0012 (18)	0.0081 (16)	0.0073 (14)
O13	0.0292 (18)	0.0345 (19)	0.055 (2)	0.0018 (16)	0.0118 (16)	0.0180 (17)
O14	0.073 (3)	0.0296 (19)	0.055 (3)	−0.014 (2)	0.015 (2)	0.0156 (18)
O21	0.043 (2)	0.0311 (16)	0.0287 (16)	0.0032 (15)	0.0130 (14)	0.0087 (13)
N22	0.034 (2)	0.047 (2)	0.0200 (18)	0.0097 (19)	0.0086 (16)	0.0149 (17)
O23	0.041 (2)	0.049 (2)	0.041 (2)	−0.0008 (18)	0.0152 (16)	0.0213 (17)
O24	0.057 (3)	0.082 (3)	0.032 (2)	0.019 (2)	0.0210 (18)	0.017 (2)
O31	0.036 (2)	0.046 (2)	0.048 (2)	−0.0008 (17)	0.0006 (16)	0.0304 (18)
O34	0.0302 (18)	0.041 (2)	0.052 (2)	0.0042 (16)	0.0079 (16)	0.0229 (18)
N32	0.039 (2)	0.0262 (19)	0.044 (2)	0.0038 (18)	0.0202 (19)	0.0133 (18)
O33	0.053 (3)	0.041 (2)	0.115 (4)	0.002 (2)	0.037 (3)	0.040 (3)
O100	0.040 (2)	0.0368 (19)	0.0346 (18)	−0.0041 (16)	−0.0075 (15)	0.0211 (16)
N51	0.0206 (16)	0.0242 (17)	0.0193 (16)	0.0040 (14)	0.0070 (13)	0.0087 (13)
C52	0.024 (2)	0.027 (2)	0.0216 (19)	0.0023 (17)	0.0096 (16)	0.0086 (16)
N53	0.031 (2)	0.0303 (19)	0.0258 (18)	0.0062 (16)	0.0111 (15)	0.0104 (15)
C54	0.033 (2)	0.0221 (19)	0.0191 (19)	0.0000 (18)	0.0060 (16)	0.0076 (16)
N55	0.0251 (18)	0.0305 (18)	0.0228 (17)	0.0040 (15)	0.0056 (14)	0.0125 (15)
C56	0.0217 (19)	0.0206 (18)	0.0208 (19)	−0.0004 (16)	0.0067 (15)	0.0090 (15)
C61	0.0190 (19)	0.0241 (19)	0.0234 (19)	0.0051 (16)	0.0068 (15)	0.0112 (16)
N62	0.0270 (18)	0.0274 (18)	0.0222 (17)	0.0061 (15)	0.0118 (14)	0.0117 (14)
C63	0.038 (3)	0.036 (2)	0.022 (2)	0.008 (2)	0.0124 (18)	0.0104 (18)
C64	0.035 (2)	0.030 (2)	0.039 (3)	0.014 (2)	0.021 (2)	0.0143 (19)
C65	0.029 (2)	0.039 (3)	0.039 (3)	0.012 (2)	0.009 (2)	0.017 (2)
C66	0.025 (2)	0.039 (2)	0.028 (2)	0.009 (2)	0.0063 (17)	0.0147 (19)
C71	0.025 (2)	0.026 (2)	0.027 (2)	0.0043 (18)	0.0102 (17)	0.0109 (17)
N72	0.0247 (19)	0.033 (2)	0.032 (2)	0.0061 (16)	0.0087 (15)	0.0149 (16)
C73	0.026 (2)	0.050 (3)	0.041 (3)	0.013 (2)	0.010 (2)	0.023 (2)
C74	0.027 (2)	0.052 (3)	0.057 (3)	0.015 (2)	0.013 (2)	0.030 (3)
C75	0.038 (3)	0.045 (3)	0.060 (4)	0.022 (3)	0.029 (3)	0.023 (3)
C76	0.035 (3)	0.042 (3)	0.038 (3)	0.012 (2)	0.016 (2)	0.012 (2)
C81	0.041 (3)	0.024 (2)	0.019 (2)	0.0030 (19)	0.0094 (18)	0.0078 (16)
N82	0.044 (3)	0.051 (3)	0.025 (2)	0.010 (2)	0.0083 (18)	0.0185 (19)
C83	0.052 (3)	0.070 (4)	0.034 (3)	0.017 (3)	0.007 (2)	0.028 (3)
C84	0.070 (4)	0.060 (4)	0.024 (2)	0.015 (3)	0.011 (2)	0.022 (2)
C85	0.059 (4)	0.049 (3)	0.035 (3)	0.011 (3)	0.027 (3)	0.018 (2)
C86	0.040 (3)	0.041 (3)	0.028 (2)	0.002 (2)	0.014 (2)	0.013 (2)
O300	0.056 (3)	0.044 (2)	0.053 (2)	0.008 (2)	0.014 (2)	0.0151 (19)
O200	0.097 (4)	0.050 (3)	0.080 (3)	−0.003 (3)	−0.019 (3)	0.042 (3)

Geometric parameters (Å, º)

Sm—O100	2.420 (4)	N53—C54	1.325 (7)
Sm—O21	2.491 (4)	C54—N55	1.348 (6)
Sm—O11	2.497 (5)	C54—C81	1.487 (6)
Sm—O31	2.500 (4)	N55—C56	1.333 (6)
Sm—O23	2.544 (4)	C56—C61	1.483 (6)
Sm—O13	2.552 (4)	C61—N62	1.347 (6)
Sm—N51	2.571 (4)	C61—C66	1.387 (7)
Sm—O34	2.615 (4)	N62—C63	1.336 (6)
Sm—N72	2.632 (4)	C63—C64	1.386 (7)
Sm—N62	2.644 (5)	C64—C65	1.359 (7)
O11—N12	1.258 (6)	C65—C66	1.397 (7)
N12—O14	1.212 (6)	C71—N72	1.359 (6)
N12—O13	1.249 (6)	C71—C76	1.381 (7)
O21—N22	1.291 (5)	N72—C73	1.340 (7)
N22—O24	1.206 (6)	C73—C74	1.390 (8)
N22—O23	1.254 (6)	C74—C75	1.351 (9)
O31—N32	1.265 (6)	C75—C76	1.399 (8)
O34—N32	1.238 (6)	C81—N82	1.340 (7)
N32—O33	1.239 (6)	C81—C86	1.383 (7)
N51—C56	1.338 (6)	N82—C83	1.340 (7)
N51—C52	1.349 (5)	C83—C84	1.377 (9)
C52—N53	1.331 (6)	C84—C85	1.354 (10)
C52—C71	1.480 (7)	C85—C86	1.377 (8)
O100—Sm—O21	78.72 (15)	O23—N22—O21	115.4 (4)
O100—Sm—O11	69.51 (14)	N22—O23—Sm	96.3 (3)
O21—Sm—O11	134.53 (14)	N32—O31—Sm	99.0 (3)
O100—Sm—O31	120.05 (13)	N32—O34—Sm	94.1 (3)
O21—Sm—O31	74.27 (15)	O33—N32—O34	123.3 (5)
O11—Sm—O31	150.36 (16)	O33—N32—O31	119.2 (5)
O100—Sm—O23	76.90 (17)	O34—N32—O31	117.5 (4)
O21—Sm—O23	50.57 (13)	O33—N32—Sm	175.4 (4)
O11—Sm—O23	90.13 (14)	O34—N32—Sm	61.3 (2)
O31—Sm—O23	118.91 (14)	O31—N32—Sm	56.2 (2)
O100—Sm—O13	107.45 (15)	C56—N51—C52	115.3 (4)
O21—Sm—O13	116.66 (13)	C56—N51—Sm	122.3 (3)
O11—Sm—O13	49.42 (14)	C52—N51—Sm	122.3 (3)
O31—Sm—O13	132.49 (13)	N53—C52—N51	123.9 (4)
O23—Sm—O13	69.14 (14)	N53—C52—C71	118.1 (4)
O100—Sm—N51	141.02 (14)	N51—C52—C71	118.0 (4)
O21—Sm—N51	136.49 (13)	C54—N53—C52	116.3 (4)
O11—Sm—N51	86.11 (13)	N53—C54—N55	124.6 (4)
O31—Sm—N51	69.47 (13)	N53—C54—C81	117.9 (4)
O23—Sm—N51	134.94 (14)	N55—C54—C81	117.5 (4)
O13—Sm—N51	74.70 (12)	C56—N55—C54	115.0 (4)
O100—Sm—O34	70.80 (14)	N55—C56—N51	124.8 (4)
O21—Sm—O34	65.91 (13)	N55—C56—C61	117.5 (4)
O11—Sm—O34	127.47 (14)	N51—C56—C61	117.7 (4)
O31—Sm—O34	49.40 (13)	N62—C61—C66	122.7 (4)
O23—Sm—O34	112.66 (14)	N62—C61—C56	117.1 (4)
O13—Sm—O34	176.78 (11)	C66—C61—C56	120.1 (4)
N51—Sm—O34	104.87 (12)	C63—N62—C61	117.4 (4)
O100—Sm—N72	80.37 (16)	C63—N62—Sm	122.5 (3)
O21—Sm—N72	134.74 (13)	C61—N62—Sm	119.4 (3)
O11—Sm—N72	71.23 (14)	N62—C63—C64	123.0 (4)
O31—Sm—N72	82.45 (15)	C65—C64—C63	119.7 (4)
O23—Sm—N72	154.59 (14)	C64—C65—C66	118.6 (5)
O13—Sm—N72	107.76 (14)	C61—C66—C65	118.6 (4)
N51—Sm—N72	62.77 (13)	N72—C71—C76	122.8 (5)
O34—Sm—N72	69.42 (15)	N72—C71—C52	116.1 (4)
O100—Sm—N62	154.48 (13)	C76—C71—C52	121.2 (4)
O21—Sm—N62	83.53 (13)	C73—N72—C71	117.0 (4)
O11—Sm—N62	112.75 (13)	C73—N72—Sm	122.3 (3)
O31—Sm—N62	71.46 (13)	C71—N72—Sm	120.7 (3)
O23—Sm—N62	77.67 (14)	N72—C73—C74	122.4 (5)
O13—Sm—N62	64.80 (15)	C75—C74—C73	120.8 (5)
N51—Sm—N62	62.86 (11)	C74—C75—C76	117.7 (5)
O34—Sm—N62	117.96 (15)	C71—C76—C75	119.3 (5)
N72—Sm—N62	124.96 (13)	N82—C81—C86	122.1 (4)
N12—O11—Sm	99.1 (3)	N82—C81—C54	117.6 (4)
O14—N12—O13	122.2 (5)	C86—C81—C54	120.2 (5)
O14—N12—O11	123.0 (5)	C83—N82—C81	117.6 (5)
O13—N12—O11	114.8 (4)	N82—C83—C84	122.7 (6)
N12—O13—Sm	96.7 (3)	C85—C84—C83	119.5 (5)
N22—O21—Sm	97.8 (3)	C84—C85—C86	119.0 (5)
O24—N22—O23	124.0 (5)	C85—C86—C81	119.1 (5)
O24—N22—O21	120.6 (5)