Crystal structure of the coordination polymer [Fe^III ₂{Pt^II(CN)₄}₃]

Abstract

The title complex, poly[dodeca-μ-cyanido-diiron(III)triplat­inum(II)], [Fe^III ₂{Pt^II(CN)₄}₃], has a three-dimensional polymeric structure. It is built-up from square-planar [Pt^II(CN)₄]²⁻ anions (point group symmetry 2/m) bridging cationic [Fe^IIIPt^II(CN)₄]⁺ _∞ layers extending in the bc plane. The Fe^II atoms of the layers are located on inversion centres and exhibit an octa­hedral coordination sphere defined by six N atoms of cyanide ligands, while the Pt^II atoms are located on twofold rotation axes and are surrounded by four C atoms of the cyanide ligands in a square-planar coordination. The geometrical preferences of the two cations for octa­hedral and square-planar coordination, respectively, lead to a corrugated organisation of the layers. The distance between neighbouring [Fe^IIIPt^II(CN)₄]⁺ _∞ layers corresponds to the length a/2 = 8.0070 (3) Å, and the separation between two neighbouring Pt^II atoms of the bridging [Pt^II(CN)₄]²⁻ groups corresponds to the length of the c axis [7.5720 (2) Å]. The structure is porous with accessible voids of 390 ų per unit cell.

Related literature  

Coordination compounds have inter­esting properties in catal­ysis (Kanderal et al., 2005 ▸; Penkova et al., 2009 ▸) or as photoactive materials (Yan et al., 2012 ▸). Magnetically active polycyanidometallate network complexes of Fe^II [Fe^II L ₂{M ^I(CN)₂}₂] or [Fe^II L ₂{M ^II(CN)₄}] (M ^I = Ag, Au; M ^II = Ni, Pd, Pt; L = N-heterocyclic ligand) have been studied because they show versatile polymeric structures (Piñeiro-López et al. 2014 ▸; Seredyuk et al., 2007 ▸, 2009 ▸), spin transition (Muñoz & Real, 2013 ▸) and functionalities such as sorption–desorption of organic and inorganic mol­ecules (Muñoz & Real, 2013 ▸) or reversible chemosorption (Arcís-Castillo et al., 2013 ▸).

Experimental  

Crystal data  

• [Fe₂Pt₃(CN)₁₂]

• M _r = 1009.18

• Monoclinic,

• a = 16.0140 (5) Å

• b = 13.8250 (5) Å

• c = 7.5720 (2) Å

• β = 102.946 (2)°

• V = 1633.78 (9) ų

• Z = 2

• Mo Kα radiation

• μ = 13.68 mm⁻¹

• T = 293 K

• 0.04 × 0.04 × 0.02 mm

Data collection  

• Oxford Diffraction Gemini S Ultra diffractometer

• Absorption correction: multi-scan (Blessing, 1995 ▸) T _min = 0.611, T _max = 0.772

• 3358 measured reflections

• 1909 independent reflections

• 1568 reflections with I > 2σ(I)

• R _int = 0.038

Refinement  

• R[F ² > 2σ(F ²)] = 0.038

• wR(F ²) = 0.106

• S = 0.97

• 1909 reflections

• 71 parameters

• Δρ_max = 1.25 e Å⁻³

• Δρ_min = −1.33 e Å⁻³

Data collection: COLLECT (Nonius, 1999 ▸); cell refinement: SCALEPACK (Otwinowski & Minor, 1997 ▸); data reduction: DENZO (Otwinowski & Minor, 1997 ▸) and SCALEPACK; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▸); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▸); molecular graphics: DIAMOND (Brandenburg, 1999 ▸); software used to prepare material for publication: WinGX (Farrugia, 2012 ▸).

Supplementary Material

CCDC reference: 1036669

Additional supporting information: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

S1. Synthesis and crystallization

Single crystals of the title compound were grown using a slow diffusion technique. During the reaction time a side product had formed serendipitously due to oxidation of the initial Fe^II salt. One side of a multi-arm shaped vessel contained (NH₄)₂Fe(SO₄)₂·6H₂O (20 mg, 51 mmol) dissolved in water (0.5 mL). The second arm contained K₂[Pt(CN)₄]·3H₂O (22 mg, 51 mmol) in water (0.5 ml). The vessel was filled with a water/methanol (1:1) solution. Square shaped orange crystals suitable for single crystal X-ray analysis were obtained after several weeks.

S2. Refinement

The highest and lowest remaining electron density are located 3.66 and 0.83 Å, respectively, from the Pt atom. The highest electron densities are connected with positions in the voids of the framework. However, modelling of the electron density e.g. under consideration of disordered (partially occupied) water molecules lead to implausible models.

Figures

Fig. 1.

Displacement ellipsoid plot (30% probability level) of the principal building units of the structure of the title compound. [Symmetry codes: (i) 1/2 + x, 1/2 + y, 1 + z; (ii) 0.5 – x, 1/2 + y, 1 – z, (iii) x, 1 – y, 1 + z.]

Fig. 2.

A fragment of three-dimentional coordination polymer of the title compound in a perspective view along c. Polyhedra correspond to FeN6 and PtC4 chromophores.

Crystal data

[Fe2Pt3(CN)12]	F(000) = 884
Mr = 1009.18	Dx = 2.051 Mg m−3
Monoclinic, C2/m	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2y	Cell parameters from 200 reflections
a = 16.0140 (5) Å	θ = 12–20°
b = 13.8250 (5) Å	µ = 13.68 mm−1
c = 7.5720 (2) Å	T = 293 K
β = 102.946 (2)°	Prismatic, orange
V = 1633.78 (9) Å3	0.04 × 0.04 × 0.02 mm
Z = 2

Data collection

Oxford Diffraction Gemini S Ultra diffractometer	1909 independent reflections
Radiation source: fine-focus sealed tube	1568 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.038
ω scans	θmax = 27.5°, θmin = 3.0°
Absorption correction: multi-scan (Blessing, 1995)	h = −20→20
Tmin = 0.611, Tmax = 0.772	k = −17→16
3358 measured reflections	l = −9→9

Refinement

Refinement on F2	0 constraints
Least-squares matrix: full	Primary atom site location: structure-invariant direct methods
R[F2 > 2σ(F2)] = 0.038	Secondary atom site location: difference Fourier map
wR(F2) = 0.106	w = 1/[σ2(Fo2) + (0.0615P)2 + 15.455P] where P = (Fo2 + 2Fc2)/3
S = 0.97	(Δ/σ)max < 0.001
1909 reflections	Δρmax = 1.25 e Å−3
71 parameters	Δρmin = −1.33 e Å−3
0 restraints

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
Pt1	0.0000	0.0000	0.0000	0.02376 (17)
Pt2	0.19452 (3)	0.5000	0.47749 (5)	0.02524 (16)
Fe	0.2500	0.2500	0.0000	0.0215 (3)
N1	0.1335 (5)	0.1622 (5)	−0.0284 (10)	0.0368 (17)
N2	0.2081 (6)	0.3449 (5)	0.1843 (10)	0.0400 (18)
N3	0.3039 (6)	0.1577 (5)	0.2273 (10)	0.0385 (17)
C1	0.0859 (5)	0.1023 (6)	−0.0190 (12)	0.0310 (17)
C2	0.2001 (6)	0.4002 (6)	0.2915 (11)	0.0335 (19)
C3	0.3072 (6)	0.1012 (6)	0.3373 (10)	0.0312 (18)

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Pt1	0.0208 (3)	0.0167 (3)	0.0343 (3)	0.000	0.0073 (2)	0.000
Pt2	0.0389 (3)	0.0182 (2)	0.0195 (2)	0.000	0.00824 (18)	0.000
Fe	0.0294 (8)	0.0165 (7)	0.0199 (7)	−0.0040 (6)	0.0083 (6)	−0.0004 (5)
N1	0.041 (4)	0.026 (4)	0.042 (4)	−0.009 (3)	0.008 (4)	−0.002 (3)
N2	0.056 (5)	0.030 (4)	0.038 (4)	−0.004 (4)	0.017 (4)	−0.006 (3)
N3	0.053 (5)	0.026 (4)	0.037 (4)	0.002 (4)	0.011 (4)	0.006 (3)
C1	0.028 (4)	0.023 (4)	0.043 (4)	0.000 (3)	0.011 (4)	0.004 (3)
C2	0.050 (6)	0.026 (4)	0.026 (4)	0.003 (4)	0.012 (4)	−0.001 (3)
C3	0.045 (5)	0.021 (4)	0.025 (4)	−0.001 (4)	0.004 (4)	0.000 (3)

Geometric parameters (Å, º)

Pt1—C1	2.000 (8)	Fe—N2	2.130 (7)
Pt1—C1i	2.000 (8)	Fe—N3vii	2.161 (7)
Pt1—C1ii	2.000 (8)	Fe—N3	2.161 (7)
Pt1—C1iii	2.000 (8)	Fe—N1vii	2.195 (7)
Pt2—C3iv	1.986 (8)	Fe—N1	2.195 (7)
Pt2—C3v	1.986 (8)	N1—C1	1.139 (10)
Pt2—C2	1.988 (8)	N2—C2	1.143 (11)
Pt2—C2vi	1.988 (8)	N3—C3	1.134 (10)
Fe—N2vii	2.130 (7)	C3—Pt2v	1.986 (8)
C1—Pt1—C1i	90.0 (5)	N3vii—Fe—N3	180.0 (3)
C1—Pt1—C1ii	180.0 (6)	N2vii—Fe—N1vii	91.1 (3)
C1i—Pt1—C1ii	90.0 (5)	N2—Fe—N1vii	88.9 (3)
C1—Pt1—C1iii	90.0 (5)	N3vii—Fe—N1vii	86.0 (3)
C1i—Pt1—C1iii	180.0 (6)	N3—Fe—N1vii	94.0 (3)
C1ii—Pt1—C1iii	90.0 (5)	N2vii—Fe—N1	88.9 (3)
C3iv—Pt2—C3v	89.6 (4)	N2—Fe—N1	91.1 (3)
C3iv—Pt2—C2	178.1 (4)	N3vii—Fe—N1	94.0 (3)
C3v—Pt2—C2	91.2 (3)	N3—Fe—N1	86.0 (3)
C3iv—Pt2—C2vi	91.2 (3)	N1vii—Fe—N1	180.0 (2)
C3v—Pt2—C2vi	178.1 (4)	C1—N1—Fe	164.2 (7)
C2—Pt2—C2vi	87.9 (5)	C2—N2—Fe	168.3 (8)
N2vii—Fe—N2	180.0 (5)	C3—N3—Fe	159.4 (8)
N2vii—Fe—N3vii	88.3 (3)	N1—C1—Pt1	178.3 (7)
N2—Fe—N3vii	91.7 (3)	N2—C2—Pt2	175.9 (9)
N2vii—Fe—N3	91.7 (3)	N3—C3—Pt2v	176.4 (8)
N2—Fe—N3	88.3 (3)

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