Syntheses, Raman spectroscopy and crystal structures of alkali hexa­fluorido­rhenates(IV) revisited

Louis-Jean, J.; Mariappan Balasekaran, S.; Smith, D.; Salamat, A.; Pham, C.T.; Poineau, F.

doi:10.1107/S2056989018005297

research communications

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 74| Part 5| May 2018| Pages 646-649

https://doi.org/10.1107/S2056989018005297

Open

access

Syntheses, Raman spectroscopy and crystal structures of alkali hexafluoridorhenates(IV) revisited

James Louis-Jean,^a Samundeeswari Mariappan Balasekaran,^a ^* Dean Smith,^b Ashkan Salamat,^b Chien Thang Pham ^c and Frederic Poineau ^a

^aDepartment of Chemistry, University of Nevada Las Vegas, 4505 South Maryland Parkway, Las Vegas, Nevada, 89154, United States, ^bDepartment of Physics and Astronomy and HiPSEC, University of Nevada Las Vegas, 4505 South Maryland Parkway, Las Vegas, Nevada, 89154, United States, and ^cDepartment of Chemistry, Hanoi University of Science, Hanoi, Vietnam
^*Correspondence e-mail: m.b.eswari@unlv.edu

Edited by M. Weil, Vienna University of Technology, Austria (Received 17 December 2017; accepted 3 April 2018; online 6 April 2018)

The A₂[ReF₆] (A = K, Rb and Cs) salts are isotypic and crystallize in the trigonal space group type P $[\overline{3}]$ m1, adopting the K₂[GeF₆] structure type. Common to all A₂[ReF₆] structures are slightly distorted octahedral [ReF₆]²⁻ anions with an average Re—F bond length of 1.951 (8) Å. In those salts, symmetry lowering on the local [ReF₆]²⁻ anions from O_h (free anion) to D_3d (solid-state structure) occur. The distortions of the [ReF₆]²⁻ anions, as observed in their Raman spectra, are correlated to the size of the counter-cations.

Keywords: rhenium; fluorine; crystal structure; Raman spectroscopy; isotypism.

CCDC references: 1834616; 1834615; 1834614

1. Chemical context

The hexafluoridorhenate(IV) anion has been known for 80 years but its chemistry is understudied with respect to the heavier halogen analogs (Ruff & Kwasnik, 1934 ). The scarcity of [ReF₆]²⁻ salts is attributed to the difficulties in their preparation and purification. K₂[ReF₆] was the first hexafluoridorhenate(IV) salt to be reported; it was prepared from the solid-state melting reaction (SSMR) of K₂[ReBr₆] with KHF₂ (Ruff & Kwasnik, 1934). Almost two decades later, ten salts comprising the [ReF₆]^2– anion and with different counter-cations (Rb⁺, Cs⁺, PPh₄⁺ (Ph = C₆H₅), [Ni(NH₃)₆]²⁺, [Co(NH₃)₆]³⁺, {[Co(NH₃)₆](NO₃)}²⁺, {[Cr(NH₃)₆](NO₃)}²⁺, [Co(NH₃)₅Cl]²⁺, [Cr(NH₃)₅Cl]²⁺, [Co(NH₃)₄(CO₃)]²⁺) had been reported (Peacock, 1956 ; Weise, 1956 ; Pedersen et al., 2014 ; Brauer & Allardt, 1962 ). Those salts were prepared by cation metathesis starting from (NH₄)₂[ReF₆] or K₂[ReF₆]. However, the synthetic procedure to prepare (NH₄)₂[ReF₆] or K₂[ReF₆] was not explained in detail. To date, only the structures of two [ReF₆]²⁻ salts have been characterized by single crystal X-ray diffraction (SCXRD): K₂[ReF₆] (measured at 292 K) and (PPh₄)₂[ReF₆]·H₂O (measured at 122 K) (Clark & Russell, 1978 ; Pedersen et al., 2014). Similarly, the synthesis of the K₂[TcF₆] congener, which was reported in 1963, involves the SSMR of K₂[TcBr₆] with KHF₂ followed by an aqueous work-up (Schwochau & Herr, 1963 ). However, [TcF₆]²⁻ salts have been reinvestigated recently (Balasekaran et al., 2013 ), and various routes for the different salts of A₂[TcF₆] [A = Na, K, Rb, Cs and N(CH₃)₄] were reported. These salts were characterized by Raman and IR spectroscopy and by SCXRD. The A₂[ReF₆] salts could serve as suitable precursors to explore the chemistry of rhenium in the oxidation state IV.

Here, we revisited the synthesis of A₂[ReF₆] (A = K, Rb, Cs) salts and report their crystal structures determined from single crystal data, and their Raman spectra.

2. Structural commentary

The title alkaline metal salts A₂[ReF₆] (A = K, Rb, Cs) are isotypic. They adopt the K₂[GeF₆] structure type (Hoard & Vincent, 1939 ) and crystallize in the trigonal space group type P $[\overline{3}]$ m1 (Table 1), just like the related A₂[TcF₆] (A = K, Rb, Cs) compounds (Balasekaran et al., 2013). Selected bond lengths and angles of the series of [ReF₆]²⁻ anions of the present work and the reported [TcF₆]²⁻ salts (Balasekaran et al., 2013) are presented in Table 1. Representative for all other title compounds, the [ReF₆]²⁻ anion of the Cs₂[ReF₆] salt is given in Fig. 1. The Re^IV atom is located on a position with site symmetry $[\overline{3}]$ m. (Wyckoff position 1a) at the origin of the trigonal unit cell. The six symmetry-related fluorine ligands form a slightly distorted octahedral coordination sphere around the rhenium(IV) atom. The Re—F bond lengths for the K, Rb, and Cs salts of [ReF₆]²⁻, 1.948 (3), 1.945 (7) and 1.9594 (18) Å, respectively, are longer than the Tc—F bond lengths for the congener K, Rb, and Cs salts of [TcF₆]²⁻, 1.928 (1), 1.933 (3), and 1.935 (5) Å, respectively (Balasekaran et al., 2013).

Table 1
Structural details (Å, °) of the [ReF₆]²⁻ anion in this study and of the related anion in [TcF₆]²⁻ salts^a

	M—F, M = Re	F—M—F, M = Re	M—F, M = Tc	F—M—F, M = Tc
K₂[MF₆]	1.948 (3)	86.08 (12), 93.92 (12), 180	1.928 (6)	86.93 (5), 93.07 (5), 180
Rb₂[MF₆]	1.945 (7)	86.5 (3), 93.5 (3), 180	1.933 (3)	87.2 (2), 92.8 (2), 180
Cs₂[MF₆]	1.9594 (18)	86.86 (7), 93.14 (7), 180	1.935 (5)	87.8 (2), 92.2 (2), 180
Note: (a) Balasekaran et al. (2013).

Figure 1
Representation of the [ReF₆]²⁻ anion in Cs₂[ReF₆]. Displacement ellipsoids are drawn at the 50% probability level. [Symmetry codes: (i) −x, −y, −z; (ii) x − y, x, −z; (iii) −x + y, −x, z; (iv) −y, x − y, z; (v) y, −x + y, −z.]

In A₂[ReF₆] (A = K⁺, Rb⁺, Cs⁺), each cation is located on a position with site symmetry 3m. (Wyckoff position 2d) and is surrounded by twelve neighboring F atoms resulting in a [3 + 6 + 3] arrangement with three groups of fluoride ligands with distances of 3.0955 (19) Å (three of such), 3.1655 (6) Å (six of such), and 3.224 (2) Å (three of such) for the Cs⁺ salt as a representative of the three [ReF₆]²⁻ salts. These bond-length distributions are also found in the K⁺ and Rb⁺ salts of the [ReF₆]²⁻ complexes. This correlates well and confirms that A₂[ReF₆] salts are isotypic with K₂[GeF₆] and the congener A₂[TcF₆] (A = K⁺, Rb⁺, Cs⁺) (Balasekaran et al., 2013; Hoard & Vincent, 1939). In comparison with the previous structure determination of K₂[ReF₆] (Clark & Russell, 1978), the current redetermination resulted in better reliability factors, together with a more precise determination of lattice parameters and atomic coordinates.

3. Raman spectroscopy

As reported previously for K₂[ReF₆] and A₂[TcF₆] (A = K, Rb, Cs) (Bettinelli et al., 1987 ; Balasekaran et al., 2013), the [ReF₆]²⁻ anions are compressed along the crystallographic c axis, thus lowering the ideal molecular symmetry of the [ReF₆]²⁻ anions from O_h to D_3d in the solid state. The representive unit-cell plot of Cs₂[ReF₆] is given in Fig. 2. The effect of symmetry lowering among the alkali metal salts of [TcF₆]²⁻ and its correlation with the vibrational spectra are well described (Balasekaran et al., 2013). Here, a similar trend occurs for the A₂[ReF₆] series (A = K, Rb, Cs; Fig. 3). In the case of K₂[ReF₆], the Raman spectrum exhibits four bands at 624, 539, 244 and 224 cm⁻¹. The latter two vibrations correspond to the F_2g band split due to the symmetry lowering. In the Raman spectra of A₂[MF₆] complexes (A = K, Rb, Cs; M = Tc, Re), the F_2g splitting decreases from K₂[ReF₆] to Cs₂[ReF₆] due to differences in M—F bond length. Furthermore, the slight increase of M—F bond lengths from K₂[MF₆] to Cs₂[MF₆] are well represented in the Raman spectra which causes the Raman bands to shift to lower wavenumbers.

Figure 2
A packing diagram of Cs₂[ReF₆]. Displacement ellipsoids are drawn at the 50% probability level.

Figure 3
Raman spectra of A₂[ReF₆] (A = K, Rb, Cs).

4. Synthesis and crystallization

Ammonium perrhenate, ammonium bifluoride, potassium fluoride, rubidium fluoride, cesium fluoride, and hydrobromic acid (48%) were purchased from Sigma Aldrich and used without any further purification. This work was performed in a well-ventilated fume hood due to the corrosive nature of bifluoride. K₂[ReBr₆] was prepared as described in the literature (Watt et al., 1963 ), and the detailed synthesis of A₂[ReF₆] (A = K, Rb, Cs) is described below. Single crystals of A₂[ReF₆] (A = K, Rb, Cs) were obtained by slow evaporation at room temperature of an aqueous solution of the respective salt.

Synthesis of K₂[ReF₆]

K₂[ReF₆] was prepared by melting K₂[ReBr₆] (2 g, 2.69 mmol) with excess KHF₂ (14 g, 0.18 mol) in a nickel crucible at 673 K for 30 min in a box furnace. The resulting greyish solid product formed was allowed to cool to room temperature and was washed first with MeOH (4 × 10 ml). Subsequently, the product was washed with several aliquots of an H₂O/MeOH mixture (3 × 5 ml, 1:4 volume ratios) and centrifuged. The pink solid obtained was dissolved in warm water (5–10 ml, 353 K) and evaporated slowly at room temperature. The resultant pink crystals of K₂[ReF₆] were recrystallized from warm water (5 ml, 353 K) and colorless crystals of K₂[ReF₆] were obtained. Yield: 661 mg, 1.7 mmol (65%). IR (KBr, cm⁻¹): 518, 484 sh (Re—F).

Syntheses of A₂[ReF₆] (A = Rb, Cs) salts

K₂[ReF₆] (151 mg, 0.4 mmol) was dissolved in 4 ml of hot water (353 K). MF (M = Rb, Cs) (0.8 mmol) dissolved in 1 ml of hot water (353 K) was added dropwise. The solution was allowed to evaporate slowly at room temperature. Crystals of Rb₂[ReF₆] and Cs₂[ReF₆] were formed in 24 h and washed first with cold water (3 × 2 ml) to remove other fluoride impurities followed by isopropanol (3 × 1 ml), and diethyl ether (3 × 1 ml). Rb₂[ReF₆] yield: 156 mg, 0.33 mmol (83%). IR (KBr, cm⁻¹): 521 (Re—F). Cs₂[ReF₆] yield: 175 mg, 0.276 mmol (77%). IR (KBr, cm⁻¹): 507, 480 sh (Re—F).

IR spectra were measured on a Shimadzu IR Affinity-1 spectrometer between 400 and 4000 cm⁻¹. Raman spectra were recorded on a HORIBA T64000 triple spectrometer operating at 30 mW in subtractive mode. The spectra were taken from pure single crystals at room temperature using the 514.5 nm (Kr/Ar) laser line.

5. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2.

Table 2
Experimental details

	K₂[ReF₆]	Rb₂[ReF₆]	Cs₂[ReF₆]
Crystal data
M_r	378.40	471.14	566.02
Crystal system, space group	Trigonal, P $[\overline{3}]$ m1	Trigonal, P $[\overline{3}]$ m1	Trigonal, P $[\overline{3}]$ m1
Temperature (K)	100	100	100
a, c (Å)	5.834 (2), 4.546 (2)	5.9926 (13), 4.7177 (10)	6.268 (1), 4.931 (1)
V (Å³)	134.00 (11)	146.72 (7)	167.77 (6)
Z	1	1	1
Radiation type	Mo Kα	Mo Kα	Mo Kα
μ (mm⁻¹)	24.26	37.22	28.83
Crystal size (mm)	0.10 × 0.07 × 0.04	0.08 × 0.07 × 0.04	0.25 × 0.12 × 0.11

Data collection
Diffractometer	Bruker D8 QUEST	Bruker D8 QUEST	Bruker D8 QUEST
Absorption correction	Multi-scan (SADABS; Bruker, 2015 )	Numerical (SADABS; Bruker, 2015)	Multi-scan (SADABS; Bruker, 2015)
T_min, T_max	0.14, 0.44	0.11, 0.30	0.05, 0.15
No. of measured, independent and observed [I > 2σ(I)] reflections	2148, 180, 180	1526, 115, 111	2683, 218, 218
R_int	0.054	0.073	0.040
(sin θ/λ)_max (Å⁻¹)	0.714	0.593	0.713

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.016, 0.041, 1.13	0.027, 0.074, 1.30	0.013, 0.036, 1.25
No. of reflections	180	115	218
No. of parameters	12	12	13
Δρ_max, Δρ_min (e Å⁻³)	1.80, −1.37	1.91, −1.36	0.68, −2.92
Computer programs: APEX3 and SAINT (Bruker, 2015), SHELXS (Sheldrick, 2008 ), SHELXL2014 (Sheldrick, 2015 ), DIAMOND (Brandenburg, 2007 ) and publCIF (Westrip, 2010 ).

Supporting information

CCDC references: 1834616; 1834615; 1834614

Crystal structure: contains datablocks global, global_1, global_2, SMB_K2ReF6_1, SMB_Rb2ReF6_j, SMB_Cs2ReF6_1a. DOI: https://doi.org/10.1107/S2056989018005297/wm5432sup1.cif

Structure factors: contains datablock SMB_K2ReF6_1. DOI: https://doi.org/10.1107/S2056989018005297/wm5432SMB_K2ReF6_1sup2.hkl

Structure factors: contains datablock SMB_Cs2ReF6_1a. DOI: https://doi.org/10.1107/S2056989018005297/wm5432SMB_Cs2ReF6_1asup3.hkl

Structure factors: contains datablock SMB_Rb2ReF6_j. DOI: https://doi.org/10.1107/S2056989018005297/wm5432SMB_Rb2ReF6_jsup4.hkl

Structure factors: contains datablock SMB_ReF6_f. DOI: https://doi.org/10.1107/S2056989018005297/wm5432SMB_ReF6_fsup5.hkl

Hexafluororhenate(IV) - revisited. DOI: https://doi.org/10.1107/S2056989018005297/wm5432sup6.pdf

Syntheses, Raman spectroscopy and crystal structures of alkali hexafluoridorhenates(IV) - revisited. DOI: https://doi.org/10.1107/S2056989018005297/wm5432sup7.pdf

checkCIF report

Computing details top

For all structures, data collection: APEX3 (Bruker, 2015); cell refinement: SAINT (Bruker, 2015); data reduction: SAINT (Bruker, 2015); program(s) used to solve structure: SHELXS (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: DIAMOND (Brandenburg, 2007); software used to prepare material for publication: publCIF (Westrip, 2010).

Dipotassium hexafluoridorhenate(IV) (SMB_K2ReF6_1) top

Crystal data top

K₂[ReF₆]	D_x = 4.689 Mg m⁻³
M_r = 378.40	Mo Kα radiation, λ = 0.71073 Å
Trigonal, P3m1	Cell parameters from 2236 reflections
a = 5.834 (2) Å	θ = 4.0–30.5°
c = 4.546 (2) Å	µ = 24.26 mm⁻¹
V = 134.00 (11) Å³	T = 100 K
Z = 1	Hexagonal, translucent colourless
F(000) = 167	0.10 × 0.07 × 0.04 mm

Data collection top

Bruker D8 QUEST diffractometer	180 independent reflections
Radiation source: sealed tube, Siemens KFFMo2K-90	180 reflections with I > 2σ(I)
Curved graphite monochromator	R_int = 0.054
Detector resolution: 8.3333 pixels mm^-1	θ_max = 30.5°, θ_min = 4.0°
φ and ω scans	h = −8→8
Absorption correction: multi-scan (SADABS; Bruker, 2015)	k = −8→8
T_min = 0.14, T_max = 0.44	l = −6→6
2148 measured reflections

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Primary atom site location: structure-invariant direct methods
R[F² > 2σ(F²)] = 0.016	Secondary atom site location: difference Fourier map
wR(F²) = 0.041	w = 1/[σ²(F_o²) + (0.0194P)² + 0.517P] where P = (F_o² + 2F_c²)/3
S = 1.13	(Δ/σ)_max < 0.001
180 reflections	Δρ_max = 1.80 e Å⁻³
12 parameters	Δρ_min = −1.37 e Å⁻³

Special details top

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.

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

	x	y	z	U_iso*/U_eq
Re1	0	0	0	0.00863 (14)
F1	0.3254 (6)	0.1627 (3)	0.2299 (6)	0.0137 (5)
K1	0.3333	0.6667	0.2955 (4)	0.0111 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Re1	0.00883 (16)	0.00883 (16)	0.0082 (2)	0.00441 (8)	0	0
F1	0.0119 (13)	0.0162 (10)	0.0117 (12)	0.0060 (6)	−0.0012 (10)	−0.0006 (5)
K1	0.0118 (5)	0.0118 (5)	0.0096 (6)	0.0059 (2)	0	0

Geometric parameters (Å, º) top

Re1—F1	1.948 (3)	F1—K1^viii	2.9325 (10)
Re1—F1ⁱ	1.948 (3)	F1—K1^vi	2.946 (3)
Re1—F1ⁱⁱ	1.948 (3)	K1—F1^xi	2.762 (3)
Re1—F1ⁱⁱⁱ	1.948 (3)	K1—F1^x	2.762 (3)
Re1—F1^iv	1.948 (3)	K1—F1^xii	2.762 (3)
Re1—F1^v	1.948 (3)	K1—F1^xiii	2.9325 (11)
Re1—K1ⁱ	3.6263 (13)	K1—F1^xiv	2.9325 (10)
Re1—K1^vi	3.6263 (13)	K1—F1^iv	2.9325 (11)
Re1—K1^vii	3.6263 (13)	K1—F1^xv	2.9325 (11)
Re1—K1	3.6263 (13)	K1—F1^xvi	2.9325 (11)
Re1—K1^viii	3.6263 (13)	K1—F1^xvii	2.946 (3)
Re1—K1^ix	3.6263 (13)	K1—F1ⁱⁱ	2.946 (3)
F1—K1^x	2.762 (3)	K1—F1^vi	2.946 (3)
F1—K1	2.9325 (11)

F1—Re1—F1ⁱ	180.0	K1—F1—K1^viii	168.22 (13)
F1—Re1—F1ⁱⁱ	86.08 (12)	Re1—F1—K1^vi	93.38 (11)
F1ⁱ—Re1—F1ⁱⁱ	93.92 (12)	K1^x—F1—K1^vi	105.55 (10)
F1—Re1—F1ⁱⁱⁱ	93.92 (12)	K1—F1—K1^vi	94.27 (6)
F1ⁱ—Re1—F1ⁱⁱⁱ	86.08 (12)	K1^viii—F1—K1^vi	94.27 (6)
F1ⁱⁱ—Re1—F1ⁱⁱⁱ	180.00 (19)	F1^xi—K1—F1^x	65.46 (11)
F1—Re1—F1^iv	93.92 (12)	F1^xi—K1—F1^xii	65.46 (11)
F1ⁱ—Re1—F1^iv	86.08 (12)	F1^x—K1—F1^xii	65.46 (11)
F1ⁱⁱ—Re1—F1^iv	86.08 (12)	F1^xi—K1—F1^xiii	62.44 (10)
F1ⁱⁱⁱ—Re1—F1^iv	93.92 (12)	F1^x—K1—F1^xiii	127.81 (6)
F1—Re1—F1^v	86.08 (12)	F1^xii—K1—F1^xiii	95.05 (6)
F1ⁱ—Re1—F1^v	93.92 (12)	F1^xi—K1—F1^xiv	62.44 (10)
F1ⁱⁱ—Re1—F1^v	93.92 (12)	F1^x—K1—F1^xiv	95.05 (6)
F1ⁱⁱⁱ—Re1—F1^v	86.08 (12)	F1^xii—K1—F1^xiv	127.81 (6)
F1^iv—Re1—F1^v	180.00 (7)	F1^xiii—K1—F1^xiv	58.10 (11)
F1—Re1—K1ⁱ	126.206 (14)	F1^xi—K1—F1^iv	95.05 (6)
F1ⁱ—Re1—K1ⁱ	53.794 (14)	F1^x—K1—F1^iv	127.81 (6)
F1ⁱⁱ—Re1—K1ⁱ	125.81 (9)	F1^xii—K1—F1^iv	62.44 (10)
F1ⁱⁱⁱ—Re1—K1ⁱ	54.19 (9)	F1^xiii—K1—F1^iv	61.22 (12)
F1^iv—Re1—K1ⁱ	126.205 (14)	F1^xiv—K1—F1^iv	118.98 (2)
F1^v—Re1—K1ⁱ	53.795 (14)	F1^xi—K1—F1^xv	95.05 (6)
F1—Re1—K1^vi	54.19 (9)	F1^x—K1—F1^xv	62.44 (10)
F1ⁱ—Re1—K1^vi	125.81 (9)	F1^xii—K1—F1^xv	127.81 (6)
F1ⁱⁱ—Re1—K1^vi	53.794 (14)	F1^xiii—K1—F1^xv	118.98 (2)
F1ⁱⁱⁱ—Re1—K1^vi	126.206 (14)	F1^xiv—K1—F1^xv	61.22 (12)
F1^iv—Re1—K1^vi	126.205 (14)	F1^iv—K1—F1^xv	168.22 (13)
F1^v—Re1—K1^vi	53.795 (14)	F1^xi—K1—F1^xvi	127.81 (6)
K1ⁱ—Re1—K1^vi	107.11 (3)	F1^x—K1—F1^xvi	62.44 (10)
F1—Re1—K1^vii	125.81 (9)	F1^xii—K1—F1^xvi	95.05 (6)
F1ⁱ—Re1—K1^vii	54.19 (9)	F1^xiii—K1—F1^xvi	168.22 (13)
F1ⁱⁱ—Re1—K1^vii	126.206 (14)	F1^xiv—K1—F1^xvi	118.98 (2)
F1ⁱⁱⁱ—Re1—K1^vii	53.794 (14)	F1^iv—K1—F1^xvi	118.98 (2)
F1^iv—Re1—K1^vii	53.795 (14)	F1^xv—K1—F1^xvi	58.10 (11)
F1^v—Re1—K1^vii	126.205 (14)	F1^xi—K1—F1	127.81 (6)
K1ⁱ—Re1—K1^vii	72.89 (3)	F1^x—K1—F1	95.05 (6)
K1^vi—Re1—K1^vii	180.0	F1^xii—K1—F1	62.44 (10)
F1—Re1—K1	53.794 (14)	F1^xiii—K1—F1	118.98 (2)
F1ⁱ—Re1—K1	126.206 (14)	F1^xiv—K1—F1	168.22 (13)
F1ⁱⁱ—Re1—K1	54.19 (9)	F1^iv—K1—F1	58.09 (11)
F1ⁱⁱⁱ—Re1—K1	125.81 (9)	F1^xv—K1—F1	118.98 (2)
F1^iv—Re1—K1	53.794 (14)	F1^xvi—K1—F1	61.22 (11)
F1^v—Re1—K1	126.206 (14)	F1^xi—K1—F1^xvii	105.55 (10)
K1ⁱ—Re1—K1	180.0	F1^x—K1—F1^xvii	144.70 (4)
K1^vi—Re1—K1	72.89 (3)	F1^xii—K1—F1^xvii	144.70 (4)
K1^vii—Re1—K1	107.11 (3)	F1^xiii—K1—F1^xvii	53.80 (10)
F1—Re1—K1^viii	53.795 (14)	F1^xiv—K1—F1^xvii	53.80 (10)
F1ⁱ—Re1—K1^viii	126.205 (14)	F1^iv—K1—F1^xvii	85.73 (6)
F1ⁱⁱ—Re1—K1^viii	126.206 (14)	F1^xv—K1—F1^xvii	85.73 (6)
F1ⁱⁱⁱ—Re1—K1^viii	53.794 (14)	F1^xvi—K1—F1^xvii	114.69 (6)
F1^iv—Re1—K1^viii	125.81 (9)	F1—K1—F1^xvii	114.69 (6)
F1^v—Re1—K1^viii	54.19 (9)	F1^xi—K1—F1ⁱⁱ	144.70 (4)
K1ⁱ—Re1—K1^viii	72.90 (3)	F1^x—K1—F1ⁱⁱ	144.70 (4)
K1^vi—Re1—K1^viii	72.90 (3)	F1^xii—K1—F1ⁱⁱ	105.55 (10)
K1^vii—Re1—K1^viii	107.10 (3)	F1^xiii—K1—F1ⁱⁱ	85.73 (6)
K1—Re1—K1^viii	107.10 (3)	F1^xiv—K1—F1ⁱⁱ	114.69 (6)
F1—Re1—K1^ix	126.205 (14)	F1^iv—K1—F1ⁱⁱ	53.80 (10)
F1ⁱ—Re1—K1^ix	53.795 (14)	F1^xv—K1—F1ⁱⁱ	114.69 (6)
F1ⁱⁱ—Re1—K1^ix	53.794 (14)	F1^xvi—K1—F1ⁱⁱ	85.73 (6)
F1ⁱⁱⁱ—Re1—K1^ix	126.206 (14)	F1—K1—F1ⁱⁱ	53.80 (10)
F1^iv—Re1—K1^ix	54.19 (9)	F1^xvii—K1—F1ⁱⁱ	60.91 (10)
F1^v—Re1—K1^ix	125.81 (9)	F1^xi—K1—F1^vi	144.70 (4)
K1ⁱ—Re1—K1^ix	107.10 (3)	F1^x—K1—F1^vi	105.55 (10)
K1^vi—Re1—K1^ix	107.10 (3)	F1^xii—K1—F1^vi	144.70 (4)
K1^vii—Re1—K1^ix	72.90 (3)	F1^xiii—K1—F1^vi	114.69 (6)
K1—Re1—K1^ix	72.90 (3)	F1^xiv—K1—F1^vi	85.73 (6)
K1^viii—Re1—K1^ix	180.0	F1^iv—K1—F1^vi	114.69 (6)
Re1—F1—K1^x	161.08 (14)	F1^xv—K1—F1^vi	53.80 (10)
Re1—F1—K1	93.79 (6)	F1^xvi—K1—F1^vi	53.80 (10)
K1^x—F1—K1	84.95 (6)	F1—K1—F1^vi	85.73 (6)
Re1—F1—K1^viii	93.79 (6)	F1^xvii—K1—F1^vi	60.91 (10)
K1^x—F1—K1^viii	84.95 (6)	F1ⁱⁱ—K1—F1^vi	60.91 (10)

Symmetry codes: (i) −x, −y, −z; (ii) x−y, x, −z; (iii) −x+y, −x, z; (iv) −y, x−y, z; (v) y, −x+y, −z; (vi) −x+1, −y+1, −z; (vii) x−1, y−1, z; (viii) x, y−1, z; (ix) −x, −y+1, −z; (x) −x+1, −y+1, −z+1; (xi) y, −x+y+1, −z+1; (xii) x−y, x, −z+1; (xiii) −x+y, −x+1, z; (xiv) x, y+1, z; (xv) −y+1, x−y+1, z; (xvi) −x+y+1, −x+1, z; (xvii) y, −x+y+1, −z.

Dirubidium hexafluoridorhenate(IV) (SMB_Rb2ReF6_j) top

Crystal data top

Rb₂[ReF₆]	D_x = 5.332 Mg m⁻³
M_r = 471.14	Mo Kα radiation, λ = 0.71073 Å
Trigonal, P3m1	Cell parameters from 1612 reflections
a = 5.9926 (13) Å	θ = 3.9–28.3°
c = 4.7177 (10) Å	µ = 37.22 mm⁻¹
V = 146.72 (7) Å³	T = 100 K
Z = 1	Hexagonal plate, translucent colourless
F(000) = 203	0.08 × 0.07 × 0.04 mm

Data collection top

Bruker D8 QUEST diffractometer	115 independent reflections
Radiation source: sealed tube, Siemens KFFMo2K-90	111 reflections with I > 2σ(I)
Curved graphite monochromator	R_int = 0.073
Detector resolution: 8.3333 pixels mm^-1	θ_max = 24.9°, θ_min = 3.9°
φ and ω scans	h = −7→7
Absorption correction: numerical (SADABS; Bruker, 2015)	k = −7→7
T_min = 0.11, T_max = 0.30	l = −5→5
1526 measured reflections

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Primary atom site location: heavy-atom method
R[F² > 2σ(F²)] = 0.027	Secondary atom site location: difference Fourier map
wR(F²) = 0.074	w = 1/[σ²(F_o²) + (0.0175P)² + 3.5548P] where P = (F_o² + 2F_c²)/3
S = 1.30	(Δ/σ)_max < 0.001
115 reflections	Δρ_max = 1.91 e Å⁻³
12 parameters	Δρ_min = −1.36 e Å⁻³

Special details top

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

	x	y	z	U_iso*/U_eq
Re1	0	0	0	0.0157 (5)
F1	0.3151 (14)	0.1576 (7)	0.2231 (15)	0.0151 (17)
Rb1	0.3333	0.6667	0.2971 (4)	0.0138 (6)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Re1	0.0133 (6)	0.0133 (6)	0.0205 (8)	0.0066 (3)	0	0
F1	0.015 (4)	0.017 (3)	0.012 (3)	0.0077 (19)	0.001 (3)	0.0007 (14)
Rb1	0.0131 (8)	0.0131 (8)	0.0152 (12)	0.0065 (4)	0	0

Geometric parameters (Å, º) top

Re1—F1ⁱ	1.945 (7)	F1—Rb1^viii	3.0181 (11)
Re1—F1ⁱⁱ	1.945 (7)	F1—Rb1^vi	3.058 (7)
Re1—F1ⁱⁱⁱ	1.945 (7)	Rb1—F1^xi	2.907 (7)
Re1—F1^iv	1.945 (7)	Rb1—F1^x	2.907 (7)
Re1—F1^v	1.945 (7)	Rb1—F1^xii	2.907 (7)
Re1—F1	1.945 (7)	Rb1—F1^xiii	3.0181 (11)
Re1—Rb1ⁱ	3.7330 (10)	Rb1—F1^xiv	3.0181 (11)
Re1—Rb1^vi	3.7330 (11)	Rb1—F1^v	3.0181 (11)
Re1—Rb1^vii	3.7330 (11)	Rb1—F1^xv	3.0181 (11)
Re1—Rb1	3.7330 (10)	Rb1—F1^xvi	3.0181 (11)
Re1—Rb1^viii	3.7330 (11)	Rb1—F1^xvii	3.058 (7)
Re1—Rb1^ix	3.7330 (11)	Rb1—F1ⁱⁱ	3.058 (7)
F1—Rb1^x	2.907 (7)	Rb1—F1^vi	3.058 (7)
F1—Rb1	3.0181 (11)

F1ⁱ—Re1—F1ⁱⁱ	93.5 (3)	Rb1—F1—Rb1^viii	166.2 (3)
F1ⁱ—Re1—F1ⁱⁱⁱ	86.5 (3)	Re1—F1—Rb1^vi	93.9 (2)
F1ⁱⁱ—Re1—F1ⁱⁱⁱ	180.0 (3)	Rb1^x—F1—Rb1^vi	104.5 (2)
F1ⁱ—Re1—F1^iv	93.5 (3)	Rb1—F1—Rb1^vi	94.26 (14)
F1ⁱⁱ—Re1—F1^iv	93.5 (3)	Rb1^viii—F1—Rb1^vi	94.26 (14)
F1ⁱⁱⁱ—Re1—F1^iv	86.5 (3)	F1^xi—Rb1—F1^x	65.8 (2)
F1ⁱ—Re1—F1^v	86.5 (3)	F1^xi—Rb1—F1^xii	65.8 (2)
F1ⁱⁱ—Re1—F1^v	86.5 (3)	F1^x—Rb1—F1^xii	65.8 (2)
F1ⁱⁱⁱ—Re1—F1^v	93.5 (3)	F1^xi—Rb1—F1^xiii	62.7 (2)
F1^iv—Re1—F1^v	180.0	F1^x—Rb1—F1^xiii	128.31 (8)
F1ⁱ—Re1—F1	180.0	F1^xii—Rb1—F1^xiii	96.30 (14)
F1ⁱⁱ—Re1—F1	86.5 (3)	F1^xi—Rb1—F1^xiv	62.7 (2)
F1ⁱⁱⁱ—Re1—F1	93.5 (3)	F1^x—Rb1—F1^xiv	96.30 (14)
F1^iv—Re1—F1	86.5 (3)	F1^xii—Rb1—F1^xiv	128.31 (8)
F1^v—Re1—F1	93.5 (3)	F1^xiii—Rb1—F1^xiv	56.0 (3)
F1ⁱ—Re1—Rb1ⁱ	53.64 (2)	F1^xi—Rb1—F1^v	96.30 (14)
F1ⁱⁱ—Re1—Rb1ⁱ	125.2 (2)	F1^x—Rb1—F1^v	128.31 (8)
F1ⁱⁱⁱ—Re1—Rb1ⁱ	54.8 (2)	F1^xii—Rb1—F1^v	62.7 (2)
F1^iv—Re1—Rb1ⁱ	53.64 (2)	F1^xiii—Rb1—F1^v	63.1 (3)
F1^v—Re1—Rb1ⁱ	126.36 (2)	F1^xiv—Rb1—F1^v	118.68 (6)
F1—Re1—Rb1ⁱ	126.36 (2)	F1^xi—Rb1—F1^xv	96.30 (14)
F1ⁱ—Re1—Rb1^vi	125.2 (2)	F1^x—Rb1—F1^xv	62.7 (2)
F1ⁱⁱ—Re1—Rb1^vi	53.64 (2)	F1^xii—Rb1—F1^xv	128.31 (8)
F1ⁱⁱⁱ—Re1—Rb1^vi	126.36 (2)	F1^xiii—Rb1—F1^xv	118.68 (5)
F1^iv—Re1—Rb1^vi	53.64 (2)	F1^xiv—Rb1—F1^xv	63.1 (3)
F1^v—Re1—Rb1^vi	126.36 (2)	F1^v—Rb1—F1^xv	166.2 (3)
F1—Re1—Rb1^vi	54.8 (2)	F1^xi—Rb1—F1^xvi	128.31 (8)
Rb1ⁱ—Re1—Rb1^vi	106.77 (3)	F1^x—Rb1—F1^xvi	62.7 (2)
F1ⁱ—Re1—Rb1^vii	54.8 (2)	F1^xii—Rb1—F1^xvi	96.30 (14)
F1ⁱⁱ—Re1—Rb1^vii	126.36 (2)	F1^xiii—Rb1—F1^xvi	166.2 (3)
F1ⁱⁱⁱ—Re1—Rb1^vii	53.64 (2)	F1^xiv—Rb1—F1^xvi	118.68 (6)
F1^iv—Re1—Rb1^vii	126.36 (2)	F1^v—Rb1—F1^xvi	118.68 (5)
F1^v—Re1—Rb1^vii	53.64 (2)	F1^xv—Rb1—F1^xvi	56.0 (3)
F1—Re1—Rb1^vii	125.2 (2)	F1^xi—Rb1—F1	128.31 (8)
Rb1ⁱ—Re1—Rb1^vii	73.23 (3)	F1^x—Rb1—F1	96.30 (14)
Rb1^vi—Re1—Rb1^vii	180.0	F1^xii—Rb1—F1	62.7 (2)
F1ⁱ—Re1—Rb1	126.36 (2)	F1^xiii—Rb1—F1	118.68 (6)
F1ⁱⁱ—Re1—Rb1	54.8 (2)	F1^xiv—Rb1—F1	166.2 (3)
F1ⁱⁱⁱ—Re1—Rb1	125.2 (2)	F1^v—Rb1—F1	56.0 (3)
F1^iv—Re1—Rb1	126.36 (2)	F1^xv—Rb1—F1	118.68 (5)
F1^v—Re1—Rb1	53.64 (2)	F1^xvi—Rb1—F1	63.1 (3)
F1—Re1—Rb1	53.64 (2)	F1^xi—Rb1—F1^xvii	104.5 (2)
Rb1ⁱ—Re1—Rb1	180.0	F1^x—Rb1—F1^xvii	144.30 (9)
Rb1^vi—Re1—Rb1	73.23 (3)	F1^xii—Rb1—F1^xvii	144.30 (9)
Rb1^vii—Re1—Rb1	106.77 (3)	F1^xiii—Rb1—F1^xvii	52.0 (2)
F1ⁱ—Re1—Rb1^viii	126.36 (2)	F1^xiv—Rb1—F1^xvii	52.0 (2)
F1ⁱⁱ—Re1—Rb1^viii	126.36 (2)	F1^v—Rb1—F1^xvii	85.74 (14)
F1ⁱⁱⁱ—Re1—Rb1^viii	53.64 (2)	F1^xv—Rb1—F1^xvii	85.74 (14)
F1^iv—Re1—Rb1^viii	54.8 (2)	F1^xvi—Rb1—F1^xvii	114.25 (9)
F1^v—Re1—Rb1^viii	125.2 (2)	F1—Rb1—F1^xvii	114.25 (9)
F1—Re1—Rb1^viii	53.64 (2)	F1^xi—Rb1—F1ⁱⁱ	144.30 (9)
Rb1ⁱ—Re1—Rb1^viii	73.23 (3)	F1^x—Rb1—F1ⁱⁱ	144.30 (9)
Rb1^vi—Re1—Rb1^viii	73.23 (3)	F1^xii—Rb1—F1ⁱⁱ	104.5 (2)
Rb1^vii—Re1—Rb1^viii	106.77 (3)	F1^xiii—Rb1—F1ⁱⁱ	85.74 (14)
Rb1—Re1—Rb1^viii	106.77 (3)	F1^xiv—Rb1—F1ⁱⁱ	114.25 (9)
F1ⁱ—Re1—Rb1^ix	53.64 (2)	F1^v—Rb1—F1ⁱⁱ	52.0 (2)
F1ⁱⁱ—Re1—Rb1^ix	53.64 (2)	F1^xv—Rb1—F1ⁱⁱ	114.25 (9)
F1ⁱⁱⁱ—Re1—Rb1^ix	126.36 (2)	F1^xvi—Rb1—F1ⁱⁱ	85.74 (14)
F1^iv—Re1—Rb1^ix	125.2 (2)	F1—Rb1—F1ⁱⁱ	52.0 (2)
F1^v—Re1—Rb1^ix	54.8 (2)	F1^xvii—Rb1—F1ⁱⁱ	62.2 (2)
F1—Re1—Rb1^ix	126.36 (2)	F1^xi—Rb1—F1^vi	144.30 (9)
Rb1ⁱ—Re1—Rb1^ix	106.77 (3)	F1^x—Rb1—F1^vi	104.5 (2)
Rb1^vi—Re1—Rb1^ix	106.77 (3)	F1^xii—Rb1—F1^vi	144.30 (9)
Rb1^vii—Re1—Rb1^ix	73.23 (3)	F1^xiii—Rb1—F1^vi	114.25 (9)
Rb1—Re1—Rb1^ix	73.23 (3)	F1^xiv—Rb1—F1^vi	85.74 (14)
Rb1^viii—Re1—Rb1^ix	180.0	F1^v—Rb1—F1^vi	114.25 (9)
Re1—F1—Rb1^x	161.6 (3)	F1^xv—Rb1—F1^vi	52.0 (2)
Re1—F1—Rb1	95.10 (14)	F1^xvi—Rb1—F1^vi	52.0 (2)
Rb1^x—F1—Rb1	83.70 (14)	F1—Rb1—F1^vi	85.74 (14)
Re1—F1—Rb1^viii	95.10 (14)	F1^xvii—Rb1—F1^vi	62.2 (2)
Rb1^x—F1—Rb1^viii	83.70 (14)	F1ⁱⁱ—Rb1—F1^vi	62.2 (2)

Symmetry codes: (i) −x, −y, −z; (ii) x−y, x, −z; (iii) −x+y, −x, z; (iv) y, −x+y, −z; (v) −y, x−y, z; (vi) −x+1, −y+1, −z; (vii) x−1, y−1, z; (viii) x, y−1, z; (ix) −x, −y+1, −z; (x) −x+1, −y+1, −z+1; (xi) y, −x+y+1, −z+1; (xii) x−y, x, −z+1; (xiii) −x+y, −x+1, z; (xiv) x, y+1, z; (xv) −y+1, x−y+1, z; (xvi) −x+y+1, −x+1, z; (xvii) y, −x+y+1, −z.

Dicaesium hexafluoridorhenate(IV) (SMB_Cs2ReF6_1a) top

Crystal data top

Cs₂[ReF₆]	D_x = 5.602 Mg m⁻³
M_r = 566.02	Mo Kα radiation, λ = 0.71073 Å
Trigonal, P3m1	Cell parameters from 135 reflections
a = 6.268 (1) Å	θ = 3.8–32.6°
c = 4.931 (1) Å	µ = 28.83 mm⁻¹
V = 167.77 (6) Å³	T = 100 K
Z = 1	Hexagonal plate, clear colourless
F(000) = 239	0.25 × 0.12 × 0.11 mm

Data collection top

Bruker D8 QUEST diffractometer	218 independent reflections
Radiation source: sealed tube, Siemens KFFMo2K-90	218 reflections with I > 2σ(I)
Curved graphite monochromator	R_int = 0.040
Detector resolution: 8.3333 pixels mm^-1	θ_max = 30.4°, θ_min = 3.8°
φ and ω scans	h = −8→8
Absorption correction: multi-scan (SADABS; Bruker, 2015)	k = −8→8
T_min = 0.05, T_max = 0.15	l = −7→7
2683 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)] = 0.013	w = 1/[σ²(F_o²) + (0.0181P)² + 0.1419P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.036	(Δ/σ)_max < 0.001
S = 1.25	Δρ_max = 0.68 e Å⁻³
218 reflections	Δρ_min = −2.92 e Å⁻³
13 parameters	Extinction correction: SHELXL2014 (Sheldrick, 2015)
0 restraints	Extinction coefficient: 0.029 (2)

Special details top

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

	x	y	z	U_iso*/U_eq
Re1	0	0	0	0.00427 (15)
F1	0.3027 (3)	0.15135 (17)	0.2165 (4)	0.0092 (4)
Cs1	0.3333	0.6667	0.30027 (9)	0.00615 (14)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Re1	0.00483 (16)	0.00483 (16)	0.0032 (2)	0.00241 (8)	0	0
F1	0.0088 (8)	0.0107 (6)	0.0075 (9)	0.0044 (4)	−0.0023 (6)	−0.0012 (3)
Cs1	0.00661 (16)	0.00661 (16)	0.0052 (2)	0.00331 (8)	0	0

Geometric parameters (Å, º) top

Re1—F1ⁱ	1.9594 (18)	F1—Cs1^viii	3.1655 (6)
Re1—F1ⁱⁱ	1.9594 (18)	F1—Cs1^vi	3.224 (2)
Re1—F1ⁱⁱⁱ	1.9594 (18)	Cs1—F1^xi	3.0955 (19)
Re1—F1^iv	1.9594 (18)	Cs1—F1^x	3.0955 (19)
Re1—F1^v	1.9594 (18)	Cs1—F1^xii	3.0955 (19)
Re1—F1	1.9594 (18)	Cs1—F1^xiii	3.1655 (6)
Re1—Cs1ⁱ	3.9100 (6)	Cs1—F1^xiv	3.1655 (6)
Re1—Cs1^vi	3.9100 (6)	Cs1—F1ⁱⁱⁱ	3.1655 (6)
Re1—Cs1^vii	3.9100 (6)	Cs1—F1^xv	3.1655 (6)
Re1—Cs1	3.9100 (6)	Cs1—F1^xvi	3.1655 (6)
Re1—Cs1^viii	3.9100 (6)	Cs1—F1^xvii	3.224 (2)
Re1—Cs1^ix	3.9100 (6)	Cs1—F1^iv	3.224 (2)
F1—Cs1^x	3.0955 (19)	Cs1—F1^vi	3.224 (2)
F1—Cs1	3.1655 (6)

F1ⁱ—Re1—F1ⁱⁱ	93.14 (7)	Cs1—F1—Cs1^viii	163.82 (6)
F1ⁱ—Re1—F1ⁱⁱⁱ	86.86 (7)	Re1—F1—Cs1^vi	94.78 (7)
F1ⁱⁱ—Re1—F1ⁱⁱⁱ	180.00 (4)	Cs1^x—F1—Cs1^vi	102.55 (5)
F1ⁱ—Re1—F1^iv	93.14 (7)	Cs1—F1—Cs1^vi	94.07 (3)
F1ⁱⁱ—Re1—F1^iv	93.14 (7)	Cs1^viii—F1—Cs1^vi	94.07 (3)
F1ⁱⁱⁱ—Re1—F1^iv	86.86 (7)	F1^xi—Cs1—F1^x	67.11 (6)
F1ⁱ—Re1—F1^v	86.86 (7)	F1^xi—Cs1—F1^xii	67.11 (6)
F1ⁱⁱ—Re1—F1^v	86.86 (7)	F1^x—Cs1—F1^xii	67.11 (6)
F1ⁱⁱⁱ—Re1—F1^v	93.14 (7)	F1^xi—Cs1—F1^xiii	62.38 (6)
F1^iv—Re1—F1^v	180.00 (8)	F1^x—Cs1—F1^xiii	129.122 (17)
F1ⁱ—Re1—F1	180.0	F1^xii—Cs1—F1^xiii	97.70 (3)
F1ⁱⁱ—Re1—F1	86.86 (7)	F1^xi—Cs1—F1^xiv	62.38 (6)
F1ⁱⁱⁱ—Re1—F1	93.14 (7)	F1^x—Cs1—F1^xiv	97.70 (3)
F1^iv—Re1—F1	86.86 (7)	F1^xii—Cs1—F1^xiv	129.122 (17)
F1^v—Re1—F1	93.14 (7)	F1^xiii—Cs1—F1^xiv	53.43 (7)
F1ⁱ—Re1—Cs1ⁱ	53.533 (6)	F1^xi—Cs1—F1ⁱⁱⁱ	97.70 (3)
F1ⁱⁱ—Re1—Cs1ⁱ	53.533 (6)	F1^x—Cs1—F1ⁱⁱⁱ	129.122 (17)
F1ⁱⁱⁱ—Re1—Cs1ⁱ	126.467 (6)	F1^xii—Cs1—F1ⁱⁱⁱ	62.38 (6)
F1^iv—Re1—Cs1ⁱ	124.74 (6)	F1^xiii—Cs1—F1ⁱⁱⁱ	65.44 (7)
F1^v—Re1—Cs1ⁱ	55.26 (6)	F1^xiv—Cs1—F1ⁱⁱⁱ	118.323 (15)
F1—Re1—Cs1ⁱ	126.467 (6)	F1^xi—Cs1—F1^xv	97.70 (3)
F1ⁱ—Re1—Cs1^vi	124.74 (6)	F1^x—Cs1—F1^xv	62.38 (6)
F1ⁱⁱ—Re1—Cs1^vi	53.533 (6)	F1^xii—Cs1—F1^xv	129.122 (17)
F1ⁱⁱⁱ—Re1—Cs1^vi	126.467 (6)	F1^xiii—Cs1—F1^xv	118.323 (14)
F1^iv—Re1—Cs1^vi	53.532 (6)	F1^xiv—Cs1—F1^xv	65.44 (7)
F1^v—Re1—Cs1^vi	126.468 (6)	F1ⁱⁱⁱ—Cs1—F1^xv	163.82 (6)
F1—Re1—Cs1^vi	55.26 (6)	F1^xi—Cs1—F1	129.123 (17)
Cs1ⁱ—Re1—Cs1^vi	106.554 (9)	F1^x—Cs1—F1	97.70 (3)
F1ⁱ—Re1—Cs1^vii	55.26 (6)	F1^xii—Cs1—F1	62.38 (6)
F1ⁱⁱ—Re1—Cs1^vii	126.467 (6)	F1^xiii—Cs1—F1	118.323 (15)
F1ⁱⁱⁱ—Re1—Cs1^vii	53.533 (6)	F1^xiv—Cs1—F1	163.82 (6)
F1^iv—Re1—Cs1^vii	126.468 (6)	F1ⁱⁱⁱ—Cs1—F1	53.43 (7)
F1^v—Re1—Cs1^vii	53.532 (6)	F1^xv—Cs1—F1	118.323 (15)
F1—Re1—Cs1^vii	124.74 (6)	F1^xi—Cs1—F1^xvi	129.122 (17)
Cs1ⁱ—Re1—Cs1^vii	73.446 (9)	F1^x—Cs1—F1^xvi	62.38 (6)
Cs1^vi—Re1—Cs1^vii	180.0	F1^xii—Cs1—F1^xvi	97.70 (3)
F1ⁱ—Re1—Cs1	126.467 (6)	F1^xiii—Cs1—F1^xvi	163.82 (6)
F1ⁱⁱ—Re1—Cs1	126.467 (6)	F1^xiv—Cs1—F1^xvi	118.323 (15)
F1ⁱⁱⁱ—Re1—Cs1	53.533 (6)	F1ⁱⁱⁱ—Cs1—F1^xvi	118.323 (15)
F1^iv—Re1—Cs1	55.26 (6)	F1^xv—Cs1—F1^xvi	53.43 (7)
F1^v—Re1—Cs1	124.74 (6)	F1—Cs1—F1^xvi	65.44 (7)
F1—Re1—Cs1	53.533 (6)	F1^xi—Cs1—F1^xvii	102.55 (5)
Cs1ⁱ—Re1—Cs1	180.0	F1^x—Cs1—F1^xvii	143.51 (2)
Cs1^vi—Re1—Cs1	73.447 (8)	F1^xii—Cs1—F1^xvii	143.51 (2)
Cs1^vii—Re1—Cs1	106.553 (8)	F1^xiii—Cs1—F1^xvii	49.86 (5)
F1ⁱ—Re1—Cs1^viii	126.467 (6)	F1^xiv—Cs1—F1^xvii	49.86 (5)
F1ⁱⁱ—Re1—Cs1^viii	55.26 (6)	F1ⁱⁱⁱ—Cs1—F1^xvii	85.93 (3)
F1ⁱⁱⁱ—Re1—Cs1^viii	124.74 (6)	F1^xv—Cs1—F1^xvii	85.93 (3)
F1^iv—Re1—Cs1^viii	126.467 (6)	F1—Cs1—F1^xvii	113.96 (2)
F1^v—Re1—Cs1^viii	53.533 (6)	F1^xvi—Cs1—F1^xvii	113.96 (2)
F1—Re1—Cs1^viii	53.533 (6)	F1^xi—Cs1—F1^iv	143.51 (2)
Cs1ⁱ—Re1—Cs1^viii	73.447 (8)	F1^x—Cs1—F1^iv	143.51 (2)
Cs1^vi—Re1—Cs1^viii	73.447 (9)	F1^xii—Cs1—F1^iv	102.55 (5)
Cs1^vii—Re1—Cs1^viii	106.553 (9)	F1^xiii—Cs1—F1^iv	85.93 (3)
Cs1—Re1—Cs1^viii	106.553 (9)	F1^xiv—Cs1—F1^iv	113.96 (2)
F1ⁱ—Re1—Cs1^ix	53.533 (6)	F1ⁱⁱⁱ—Cs1—F1^iv	49.86 (5)
F1ⁱⁱ—Re1—Cs1^ix	124.74 (6)	F1^xv—Cs1—F1^iv	113.96 (2)
F1ⁱⁱⁱ—Re1—Cs1^ix	55.26 (6)	F1—Cs1—F1^iv	49.86 (5)
F1^iv—Re1—Cs1^ix	53.533 (6)	F1^xvi—Cs1—F1^iv	85.93 (3)
F1^v—Re1—Cs1^ix	126.467 (6)	F1^xvii—Cs1—F1^iv	64.10 (5)
F1—Re1—Cs1^ix	126.467 (6)	F1^xi—Cs1—F1^vi	143.51 (2)
Cs1ⁱ—Re1—Cs1^ix	106.553 (8)	F1^x—Cs1—F1^vi	102.55 (5)
Cs1^vi—Re1—Cs1^ix	106.553 (9)	F1^xii—Cs1—F1^vi	143.51 (2)
Cs1^vii—Re1—Cs1^ix	73.447 (9)	F1^xiii—Cs1—F1^vi	113.96 (2)
Cs1—Re1—Cs1^ix	73.447 (9)	F1^xiv—Cs1—F1^vi	85.93 (3)
Cs1^viii—Re1—Cs1^ix	180.0	F1ⁱⁱⁱ—Cs1—F1^vi	113.96 (2)
Re1—F1—Cs1^x	162.67 (9)	F1^xv—Cs1—F1^vi	49.86 (5)
Re1—F1—Cs1	96.61 (3)	F1—Cs1—F1^vi	85.93 (3)
Cs1^x—F1—Cs1	82.30 (3)	F1^xvi—Cs1—F1^vi	49.86 (5)
Re1—F1—Cs1^viii	96.61 (3)	F1^xvii—Cs1—F1^vi	64.10 (5)
Cs1^x—F1—Cs1^viii	82.30 (3)	F1^iv—Cs1—F1^vi	64.10 (5)

Symmetry codes: (i) −x, −y, −z; (ii) y, −x+y, −z; (iii) −y, x−y, z; (iv) x−y, x, −z; (v) −x+y, −x, z; (vi) −x+1, −y+1, −z; (vii) x−1, y−1, z; (viii) x, y−1, z; (ix) −x, −y+1, −z; (x) −x+1, −y+1, −z+1; (xi) y, −x+y+1, −z+1; (xii) x−y, x, −z+1; (xiii) −x+y, −x+1, z; (xiv) x, y+1, z; (xv) −y+1, x−y+1, z; (xvi) −x+y+1, −x+1, z; (xvii) y, −x+y+1, −z.

Structural details (Å, °) of the [ReF₆]^2- anion in this study and of the related anion in [TcF₆]^2- salts^a top

	M—F, M = Re	F—M—F, M = Re	M—F, M = Tc	F—M—F, M = Tc
K₂[MF₆]	1.948 (3)	86.08 (12), 93.92 (12), 180	1.928 (6)	86.93 (5), 93.07 (5), 180
Rb₂[MF₆]	1.945 (7)	86.5 (3), 93.5 (3), 180	1.933 (3)	87.2 (2), 92.8 (2), 180
Cs₂[MF₆]	1.9594 (18)	86.86 (7), 93.14 (7), 180	1.935 (5)	87.8 (2), 92.2 (2), 180

Note: (a) Balasekaran et al. (2013).

Acknowledgements

The authors thank Ms Julie Bertoia and Mr Charles Bynum for laboratory support, and Ms Wendee Johns for administrative support.

Funding information

Funding for this research was provided by: Department of Energy - Nuclear Science and Security Consortium (award No. DE-NA0003180).

References

Balasekaran, S. M., Molski, M., Spandl, J., Hagenbach, A., Alberto, R. & Abram, U. (2013). Inorg. Chem. 52, 7094–7099. Web of Science CSD CrossRef CAS Google Scholar
Bettinelli, M., Disipio, L., Ingletto, G. & Razzetti, C. (1987). Inorg. Chim. Acta, 133, 7–9. CrossRef CAS Web of Science Google Scholar
Brandenburg, K. (2007). DIAMOND. Crystal Impact GbR, Bonn, Germany. Google Scholar
Brauer, G. & Allardt, H. D. (1962). Z. Anorg. Allg. Chem. 316, 134–140. CrossRef CAS Web of Science Google Scholar
Bruker (2015). APEX3, SAINT and SADABS. Bruker AXS Inc., Madison, WI, USA. Google Scholar
Clark, G. R. & Russell, D. R. (1978). Acta Cryst. B34, 894–895. CrossRef CAS IUCr Journals Web of Science Google Scholar
Hoard, J. L. & Vincent, W. B. (1939). J. Am. Chem. Soc. 61, 2849–2852. CrossRef CAS Google Scholar
Peacock, R. D. (1956). J. Chem. Soc. pp. 1291–1293. CrossRef Web of Science Google Scholar
Pedersen, K. S., Sigrist, M., Sorensen, M. A., Barra, A. L., Weyhermuller, T., Piligkos, S., Thuesen, C. A., Vinum, M. G., Mutka, H., Weihe, H., Clerac, R. & Bendix, J. (2014). Angew. Chem. Int. Ed. 53, 1351–1354. Web of Science CSD CrossRef CAS Google Scholar
Ruff, O. & Kwasnik, W. (1934). Z. Anorg. Allg. Chem. 219, 65–81. CrossRef CAS Google Scholar
Schwochau, K. & Herr, W. (1963). Angew. Chem. 75, 95. CrossRef Web of Science Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Sheldrick, G. M. (2015). Acta Cryst. C71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Watt, G. W., Thompson, R. J. & Gibbons, J. M. (1963). Inorganic Syntheses edited by J. Kleinberg, Vol 7, pp. 189–190. New York: McGraw-Hill. Google Scholar
Weise, E. (1956). Z. Anorg. Allg. Chem. 283, 377–389. CrossRef CAS Web of Science Google Scholar
Westrip, S. P. (2010). J. Appl. Cryst. 43, 920–925. Web of Science CrossRef CAS IUCr Journals Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 74| Part 5| May 2018| Pages 646-649

https://doi.org/10.1107/S2056989018005297

Open

access

Format		BIBTeX
		EndNote
		RefMan
		Refer
		Medline
		CIF
		SGML
		Plain Text
		Text

Format		BIBTeX
		EndNote
		RefMan
		Refer
		Medline
		CIF
		SGML
		Plain Text
		Text

Search IUCr Journals		doi		Advanced search
Author		volume	page

research communications\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Syntheses, Raman spectroscopy and crystal structures of alkali hexa­fluorido­rhenates(IV) revisited

1. Chemical context

2. Structural commentary

3. Raman spectroscopy

4. Synthesis and crystallization

5. Refinement

Supporting information

Acknowledgements

Funding information

References

research communications

Syntheses, Raman spectroscopy and crystal structures of alkali hexafluoridorhenates(IV) revisited