Zirconium tetra­chloride revisited

Zirconium tetra­chloride, ZrCl₄, is a strategic material with wide-ranging applications. Until now, only one crystallographic study on ZrCl₄ has been reported [Krebs (1970). Z. Anorg. Allg. Chem. 378, 263–272] and that was more than 40 years ago. The compound used for the previous determination was prepared from ZrO₂ and Cl₂–CCl₄, and single-crystal X-ray diffraction (SCXRD) studies on ZrCl₄ obtained from Zr metal have not yet been reported. In this context, we prepared ZrCl₄ from the reaction of Zr metal and Cl₂ gas in a sealed tube and investigated its structure at 100, 150, 200, 250, and 300 K. At 300 K, the SCXRD analysis indicates that ZrCl₄ crystallizes in the ortho­rhom­bic space group Pca2₁ [a = 6.262 (9), b = 7.402 (11), c = 12.039 (17) Å, and V = 558.0 (14) ų] and consists of infinite zigzag chains of edge-sharing ZrCl₆ octa­hedra. This chain motif is similar to that observed previously in ZrCl₄, but the structural parameters and space group differ. In the temperature range 100–300 K, no phase transformation was identified, while elongation of intra-chain Zr...Zr [3.950 (1) Å at 100 K and 3.968 (5) Å at 300 K] and inter-chain Cl...Cl [3.630 (3) Å at 100 K and 3.687 (9) Å at 300 K] distances occurred.

Computing details

For all structures, data collection: BIS (Bruker, 2016); cell refinement: APEX3 (Bruker, 2016); data reduction: SAINT (Bruker, 2015); program(s) used to solve structure: SHELXT2014 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: shelXle (Hübschle et al., 2011); software used to prepare material for publication: APEX3 (Bruker, 2016).

Zirconium tetrachloride (SMB_ZrCl4_b_100K)

Crystal data

ZrCl4	Dx = 2.849 Mg m^−3
Mr = 233.02	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pca21	Cell parameters from 2790 reflections
a = 6.2199 (9) Å	θ = 2.8–27.9°
b = 7.3301 (10) Å	µ = 3.82 mm^−1
c = 11.9153 (16) Å	T = 100 K
V = 543.25 (13) Å^3	Rectangular box, translucent colourless
Z = 4	0.09 × 0.08 × 0.06 mm
F(000) = 432

Data collection

Bruker D8 QUEST diffractometer	924 independent reflections
Radiation source: sealed tube, Siemens KFFMo2K-90	877 reflections with I > 2σ(I)
Curved graphite monochromator	Rint = 0.050
Detector resolution: 8.3333 pixels mm^-1	θmax = 24.7°, θmin = 3.4°
φ and ω scans	h = −7→7
Absorption correction: numerical (SADABS; Krause et al., 2015)	k = −8→8
Tmin = 0.63, Tmax = 0.81	l = −14→14
5240 measured reflections

Refinement

Refinement on F^2	Primary atom site location: heavy-atom method
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.035	w = 1/[σ^2(Fo^2) + (0.0547P)^2] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.084	(Δ/σ)max < 0.001
S = 1.07	Δρmax = 2.08 e Å^−3
924 reflections	Δρmin = −0.53 e Å^−3
46 parameters	Absolute structure: Flack x determined using 394 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013)
1 restraint	Absolute structure parameter: −0.05 (15)

Special details

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.

Refinement. Data collections were carried out on a Bruker APEXII system equipped with graphite-monochromated Mo Kα radiation (0.71073 Å). A nitrogen-flow Oxford Cryostream-700 was used to control the temperature. Data collections were carried out in the order 100, 150, 200, 250, and 300 K on the same crystal. Data reduction and cell refinement were performed using SAINT and the APEX3 suite (Bruker, 2016). The structure was solved with SHELXT (Sheldrick, 2015a) and an absorption correction was performed with SADABS (Sheldrick, 1999). Structure refinements against F² were carried out using the SHELXL refinement package in APEX3 (Bruker, 2016). The apparent space group for the structure at all five temperatures was suggested to be orthorhombic Pca2₁ by XPREP, which differs from that previously described (i.e. monoclinic, P2/c (Krebs, 1970). The refinement yielded R factors varying from 0.0345 at 100 K to 0.0534 at 300 K.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Zr1	0.42265 (13)	0.33389 (11)	0.49994 (14)	0.0170 (3)
Cl1	0.5727 (4)	0.1350 (3)	0.6288 (2)	0.0221 (6)
Cl2	0.0920 (4)	0.3893 (3)	0.61382 (19)	0.0189 (6)
Cl3	0.2781 (4)	0.1303 (3)	0.3723 (2)	0.0226 (6)
Cl4	0.7506 (4)	0.3924 (3)	0.38424 (18)	0.0194 (6)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Zr1	0.0132 (4)	0.0184 (5)	0.0193 (5)	0.0001 (4)	0.0003 (4)	0.0003 (6)
Cl1	0.0211 (13)	0.0236 (13)	0.0217 (13)	0.0026 (10)	−0.0024 (10)	0.0043 (10)
Cl2	0.0150 (12)	0.0217 (12)	0.0200 (14)	0.0014 (9)	0.0012 (9)	0.0022 (10)
Cl3	0.0208 (12)	0.0238 (12)	0.0231 (14)	−0.0017 (10)	−0.0020 (12)	−0.0022 (10)
Cl4	0.0153 (11)	0.0219 (12)	0.0211 (14)	−0.0019 (10)	0.0017 (11)	−0.0009 (10)

Geometric parameters (Å, º)

Zr1—Cl3	2.313 (3)	Zr1—Cl2^i	2.659 (3)
Zr1—Cl1	2.314 (3)	Zr1—Cl4^ii	2.659 (2)
Zr1—Cl2	2.497 (3)	Cl2—Zr1^ii	2.659 (3)
Zr1—Cl4	2.499 (2)	Cl4—Zr1^i	2.659 (2)
Cl3—Zr1—Cl1	100.75 (9)	Cl4—Zr1—Cl2^i	80.05 (7)
Cl3—Zr1—Cl2	98.17 (9)	Cl3—Zr1—Cl4^ii	89.40 (9)
Cl1—Zr1—Cl2	94.25 (10)	Cl1—Zr1—Cl4^ii	169.03 (11)
Cl3—Zr1—Cl4	93.74 (10)	Cl2—Zr1—Cl4^ii	80.08 (7)
Cl1—Zr1—Cl4	98.34 (9)	Cl4—Zr1—Cl4^ii	85.01 (7)
Cl2—Zr1—Cl4	160.75 (9)	Cl2^i—Zr1—Cl4^ii	81.26 (7)
Cl3—Zr1—Cl2^i	169.16 (11)	Zr1—Cl2—Zr1^ii	99.96 (9)
Cl1—Zr1—Cl2^i	89.00 (10)	Zr1—Cl4—Zr1^i	99.90 (9)
Cl2—Zr1—Cl2^i	85.69 (8)

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

Zirconium tetrachloride (SMB_ZrCl4a_a_150K)

Crystal data

ZrCl4	Dx = 2.829 Mg m^−3
Mr = 233.02	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pca21	Cell parameters from 2581 reflections
a = 6.2311 (8) Å	θ = 2.8–27.9°
b = 7.3497 (10) Å	µ = 3.79 mm^−1
c = 11.9462 (15) Å	T = 150 K
V = 547.10 (12) Å^3	Rectangular plate, translucent colourless
Z = 4	0.09 × 0.08 × 0.06 mm
F(000) = 432

Data collection

Bruker D8 QUEST diffractometer	906 independent reflections
Radiation source: sealed tube, Siemens KFFMo2K-90	853 reflections with I > 2σ(I)
Curved graphite monochromator	Rint = 0.051
Detector resolution: 8.3333 pixels mm^-1	θmax = 24.7°, θmin = 6.5°
φ and ω scans	h = −7→7
Absorption correction: numerical (SADABS; Krause et al., 2015)	k = −8→8
Tmin = 0.64, Tmax = 0.78	l = −14→14
5124 measured reflections

Refinement

Refinement on F^2	Primary atom site location: heavy-atom method
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.033	w = 1/[σ^2(Fo^2) + (0.0514P)^2] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.080	(Δ/σ)max < 0.001
S = 1.04	Δρmax = 2.08 e Å^−3
906 reflections	Δρmin = −0.52 e Å^−3
46 parameters	Absolute structure: Flack x determined using 374 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013)
1 restraint	Absolute structure parameter: −0.03 (14)

Special details

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.

Refinement. Refined as a 2-component twin.

Data collections were carried out on a Bruker APEXII system equipped with graphite-monochromated Mo Kα radiation (0.71073 Å). A nitrogen-flow Oxford Cryostream-700 was used to control the temperature. Data collections were carried out in the order 100, 150, 200, 250, and 300 K on the same crystal. Data reduction and cell refinement were performed using SAINT and the APEX3 suite (Bruker, 2016). The structure was solved with SHELXT (Sheldrick, 2015a) and an absorption correction was performed with SADABS (Sheldrick, 1999). Structure refinements against F² were carried out using the SHELXL refinement package in APEX3 (Bruker, 2016). The apparent space group for the structure at all five temperatures was suggested to be orthorhombic Pca2₁ by XPREP, which differs from that previously described (i.e. monoclinic, P2/c (Krebs, 1970). The refinement yielded R factors varying from 0.0345 at 100 K to 0.0534 at 300 K.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Zr1	0.42306 (12)	0.33410 (10)	0.50001 (13)	0.0191 (3)
Cl1	0.5726 (4)	0.1359 (3)	0.6287 (2)	0.0265 (6)
Cl2	0.0927 (4)	0.3896 (3)	0.61336 (18)	0.0211 (6)
Cl3	0.2797 (4)	0.1309 (3)	0.3725 (2)	0.0276 (6)
Cl4	0.7507 (4)	0.3926 (3)	0.38452 (18)	0.0229 (6)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Zr1	0.0150 (4)	0.0208 (5)	0.0213 (5)	0.0002 (4)	0.0005 (4)	0.0006 (5)
Cl1	0.0252 (14)	0.0281 (13)	0.0262 (14)	0.0041 (10)	−0.0028 (10)	0.0042 (11)
Cl2	0.0161 (12)	0.0250 (12)	0.0222 (13)	0.0024 (9)	0.0024 (9)	0.0035 (10)
Cl3	0.0273 (12)	0.0279 (12)	0.0277 (14)	−0.0030 (11)	−0.0037 (13)	−0.0040 (10)
Cl4	0.0184 (11)	0.0254 (11)	0.0247 (14)	−0.0022 (10)	0.0018 (11)	−0.0029 (10)

Geometric parameters (Å, º)

Zr1—Cl3	2.313 (3)	Zr1—Cl2^i	2.660 (3)
Zr1—Cl1	2.314 (3)	Zr1—Cl4^ii	2.663 (2)
Zr1—Cl2	2.497 (2)	Cl2—Zr1^ii	2.660 (3)
Zr1—Cl4	2.501 (2)	Cl4—Zr1^i	2.663 (2)
Cl3—Zr1—Cl1	100.76 (9)	Cl4—Zr1—Cl2^i	79.93 (7)
Cl3—Zr1—Cl2	98.31 (9)	Cl3—Zr1—Cl4^ii	89.43 (10)
Cl1—Zr1—Cl2	94.27 (9)	Cl1—Zr1—Cl4^ii	168.97 (10)
Cl3—Zr1—Cl4	93.60 (10)	Cl2—Zr1—Cl4^ii	79.94 (7)
Cl1—Zr1—Cl4	98.39 (9)	Cl4—Zr1—Cl4^ii	85.05 (7)
Cl2—Zr1—Cl4	160.69 (9)	Cl2^i—Zr1—Cl4^ii	81.27 (7)
Cl3—Zr1—Cl2^i	169.05 (11)	Zr1—Cl2—Zr1^ii	100.15 (9)
Cl1—Zr1—Cl2^i	88.99 (9)	Zr1—Cl4—Zr1^i	99.96 (9)
Cl2—Zr1—Cl2^i	85.81 (8)

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

Zirconium tetrachloride (SMB_ZrCl4_b_200K)

Crystal data

ZrCl4	Dx = 2.813 Mg m^−3
Mr = 233.02	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pca21	Cell parameters from 2383 reflections
a = 6.2389 (8) Å	θ = 2.8–28.4°
b = 7.3667 (10) Å	µ = 3.77 mm^−1
c = 11.9735 (16) Å	T = 200 K
V = 550.30 (13) Å^3	Rectangular box, translucent colourless
Z = 4	0.09 × 0.08 × 0.06 mm
F(000) = 432

Data collection

Bruker D8 QUEST diffractometer	934 independent reflections
Radiation source: sealed tube, Siemens KFFMo2K-90	864 reflections with I > 2σ(I)
Curved graphite monochromator	Rint = 0.049
Detector resolution: 8.3333 pixels mm^-1	θmax = 24.7°, θmin = 3.4°
φ and ω scans	h = −7→7
Absorption correction: numerical (SADABS; Krause et al., 2015)	k = −8→8
Tmin = 0.64, Tmax = 0.82	l = −14→14
5292 measured reflections

Refinement

Refinement on F^2	Primary atom site location: heavy-atom method
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.038	w = 1/[σ^2(Fo^2) + (0.0551P)^2 + 0.3988P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.095	(Δ/σ)max < 0.001
S = 1.11	Δρmax = 2.11 e Å^−3
934 reflections	Δρmin = −0.54 e Å^−3
46 parameters	Absolute structure: Flack x determined using 386 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013)
1 restraint	Absolute structure parameter: 0.18 (17)

Special details

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.

Refinement. Data collections were carried out on a Bruker APEXII system equipped with graphite-monochromated Mo Kα radiation (0.71073 Å). A nitrogen-flow Oxford Cryostream-700 was used to control the temperature. Data collections were carried out in the order 100, 150, 200, 250, and 300 K on the same crystal. Data reduction and cell refinement were performed using SAINT and the APEX3 suite (Bruker, 2016). The structure was solved with SHELXT (Sheldrick, 2015a) and an absorption correction was performed with SADABS (Sheldrick, 1999). Structure refinements against F² were carried out using the SHELXL refinement package in APEX3 (Bruker, 2016). The apparent space group for the structure at all five temperatures was suggested to be orthorhombic Pca2₁ by XPREP, which differs from that previously described (i.e. monoclinic, P2/c (Krebs, 1970). The refinement yielded R factors varying from 0.0345 at 100 K to 0.0534 at 300 K.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Zr1	0.42327 (15)	0.33461 (12)	0.50006 (16)	0.0244 (3)
Cl1	0.5717 (5)	0.1372 (4)	0.6283 (3)	0.0346 (8)
Cl2	0.0931 (4)	0.3897 (4)	0.6132 (2)	0.0278 (7)
Cl3	0.2805 (5)	0.1316 (4)	0.3725 (3)	0.0356 (7)
Cl4	0.7508 (4)	0.3931 (4)	0.3848 (2)	0.0288 (7)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Zr1	0.0189 (5)	0.0265 (5)	0.0278 (6)	0.0001 (4)	0.0001 (5)	0.0001 (7)
Cl1	0.0329 (17)	0.0368 (17)	0.0340 (17)	0.0042 (12)	−0.0045 (13)	0.0074 (13)
Cl2	0.0217 (14)	0.0330 (15)	0.0287 (16)	0.0017 (11)	0.0019 (11)	0.0050 (12)
Cl3	0.0344 (16)	0.0359 (16)	0.0365 (18)	−0.0042 (13)	−0.0012 (16)	−0.0048 (13)
Cl4	0.0229 (13)	0.0343 (14)	0.0290 (16)	−0.0017 (12)	0.0025 (13)	−0.0036 (12)

Geometric parameters (Å, º)

Zr1—Cl1	2.309 (3)	Zr1—Cl2^i	2.661 (3)
Zr1—Cl3	2.316 (3)	Zr1—Cl4^ii	2.662 (3)
Zr1—Cl2	2.499 (3)	Cl2—Zr1^ii	2.661 (3)
Zr1—Cl4	2.503 (3)	Cl4—Zr1^i	2.662 (3)
Cl1—Zr1—Cl3	100.74 (11)	Cl4—Zr1—Cl2^i	79.87 (9)
Cl1—Zr1—Cl2	94.15 (11)	Cl1—Zr1—Cl4^ii	168.98 (12)
Cl3—Zr1—Cl2	98.37 (11)	Cl3—Zr1—Cl4^ii	89.38 (12)
Cl1—Zr1—Cl4	98.49 (10)	Cl2—Zr1—Cl4^ii	79.94 (9)
Cl3—Zr1—Cl4	93.52 (12)	Cl4—Zr1—Cl4^ii	85.10 (9)
Cl2—Zr1—Cl4	160.72 (10)	Cl2^i—Zr1—Cl4^ii	81.36 (8)
Cl1—Zr1—Cl2^i	88.99 (11)	Zr1—Cl2—Zr1^ii	100.16 (11)
Cl3—Zr1—Cl2^i	169.01 (13)	Zr1—Cl4—Zr1^i	100.02 (10)
Cl2—Zr1—Cl2^i	85.88 (9)

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

Zirconium tetrachloride (SMB_ZrCl4_b_250K)

Crystal data

Cl4Zr	Dx = 2.790 Mg m^−3
Mr = 233.02	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pca21	Cell parameters from 1861 reflections
a = 6.253 (5) Å	θ = 2.8–25.8°
b = 7.383 (6) Å	µ = 3.74 mm^−1
c = 12.017 (9) Å	T = 250 K
V = 554.8 (7) Å^3	Rectangualr plate, translucent colourless
Z = 4	0.09 × 0.08 × 0.06 mm
F(000) = 432

Data collection

Bruker D8 QUEST diffractometer	934 independent reflections
Radiation source: sealed tube, Siemens KFFMo2K-90	815 reflections with I > 2σ(I)
Curved graphite monochromator	Rint = 0.063
Detector resolution: 8.3333 pixels mm^-1	θmax = 24.7°, θmin = 4.3°
φ and ω scans	h = −7→7
Absorption correction: numerical (SADABS; Krause et al., 2015)	k = −8→8
Tmin = 0.63, Tmax = 0.81	l = −14→14
5285 measured reflections

Refinement

Refinement on F^2	Primary atom site location: heavy-atom method
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.038	w = 1/[σ^2(Fo^2) + (0.0566P)^2] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.096	(Δ/σ)max < 0.001
S = 1.05	Δρmax = 2.13 e Å^−3
934 reflections	Δρmin = −0.48 e Å^−3
46 parameters	Absolute structure: Flack x determined using 351 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013)
1 restraint	Absolute structure parameter: 0.01 (15)

Special details

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.

Refinement. Data collections were carried out on a Bruker APEXII system equipped with graphite-monochromated Mo Kα radiation (0.71073 Å). A nitrogen-flow Oxford Cryostream-700 was used to control the temperature. Data collections were carried out in the order 100, 150, 200, 250, and 300 K on the same crystal. Data reduction and cell refinement were performed using SAINT and the APEX3 suite (Bruker, 2016). The structure was solved with SHELXT (Sheldrick, 2015a) and an absorption correction was performed with SADABS (Sheldrick, 1999). Structure refinements against F² were carried out using the SHELXL refinement package in APEX3 (Bruker, 2016). The apparent space group for the structure at all five temperatures was suggested to be orthorhombic Pca2₁ by XPREP, which differs from that previously described (i.e. monoclinic, P2/c (Krebs, 1970). The refinement yielded R factors varying from 0.0345 at 100 K to 0.0534 at 300 K.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Zr1	0.42359 (16)	0.33495 (13)	0.50035 (17)	0.0260 (4)
Cl2	0.0938 (5)	0.3902 (4)	0.3876 (2)	0.0303 (8)
Cl3	0.2820 (5)	0.1329 (4)	0.6274 (3)	0.0408 (9)
Cl1	0.5717 (6)	0.1375 (5)	0.3721 (3)	0.0395 (9)
Cl4	0.7504 (5)	0.3927 (4)	0.6150 (2)	0.0321 (8)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Zr1	0.0210 (5)	0.0289 (6)	0.0282 (6)	−0.0003 (5)	−0.0002 (6)	0.0007 (7)
Cl2	0.0239 (16)	0.0373 (17)	0.0296 (18)	0.0021 (13)	−0.0020 (13)	−0.0062 (14)
Cl3	0.0396 (19)	0.0415 (18)	0.041 (2)	−0.0060 (16)	0.0054 (19)	0.0064 (15)
Cl1	0.041 (2)	0.0397 (19)	0.038 (2)	0.0059 (15)	0.0033 (15)	−0.0104 (15)
Cl4	0.0263 (15)	0.0374 (16)	0.032 (2)	−0.0036 (14)	−0.0052 (15)	0.0069 (14)

Geometric parameters (Å, º)

Zr1—Cl3	2.311 (4)	Zr1—Cl2^i	2.662 (4)
Zr1—Cl1	2.315 (4)	Zr1—Cl4^ii	2.667 (3)
Zr1—Cl2	2.501 (4)	Cl2—Zr1^ii	2.662 (4)
Zr1—Cl4	2.501 (4)	Cl4—Zr1^i	2.667 (3)
Cl3—Zr1—Cl1	100.76 (13)	Cl4—Zr1—Cl2^i	79.85 (10)
Cl3—Zr1—Cl2	98.46 (13)	Cl3—Zr1—Cl4^ii	89.41 (14)
Cl1—Zr1—Cl2	94.12 (13)	Cl1—Zr1—Cl4^ii	168.86 (14)
Cl3—Zr1—Cl4	93.40 (14)	Cl2—Zr1—Cl4^ii	79.76 (10)
Cl1—Zr1—Cl4	98.47 (12)	Cl4—Zr1—Cl4^ii	85.33 (11)
Cl2—Zr1—Cl4	160.79 (11)	Cl2^i—Zr1—Cl4^ii	81.41 (11)
Cl3—Zr1—Cl2^i	168.98 (14)	Zr1—Cl2—Zr1^ii	100.26 (12)
Cl1—Zr1—Cl2^i	88.92 (14)	Zr1—Cl4—Zr1^i	100.12 (12)
Cl2—Zr1—Cl2^i	85.96 (11)

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

Zirconium tetrachloride (SMB_ZrCl4_b_300K)

Crystal data

ZrCl4	Dx = 2.773 Mg m^−3
Mr = 233.02	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pca21	Cell parameters from 1130 reflections
a = 6.262 (9) Å	θ = 2.8–24.5°
b = 7.402 (11) Å	µ = 3.71 mm^−1
c = 12.039 (17) Å	T = 300 K
V = 558.0 (14) Å^3	Rectangular box, translucent colourless
Z = 4	0.09 × 0.08 × 0.06 mm
F(000) = 432

Data collection

Bruker D8 QUEST diffractometer	949 independent reflections
Radiation source: sealed tube, Siemens KFFMo2K-90	737 reflections with I > 2σ(I)
Curved graphite monochromator	Rint = 0.093
Detector resolution: 8.3333 pixels mm^-1	θmax = 24.7°, θmin = 3.4°
φ and ω scans	h = −7→7
Absorption correction: numerical (SADABS; Krause et al., 2015)	k = −8→8
Tmin = 0.55, Tmax = 0.81	l = −14→14
5334 measured reflections

Refinement

Refinement on F^2	Primary atom site location: heavy-atom method
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.053	w = 1/[σ^2(Fo^2) + (0.0788P)^2] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.138	(Δ/σ)max < 0.001
S = 1.02	Δρmax = 2.59 e Å^−3
949 reflections	Δρmin = −0.70 e Å^−3
46 parameters	Absolute structure: Flack x determined using 284 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013)
1 restraint	Absolute structure parameter: 0.0 (3)

Special details

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.

Refinement. Data collections were carried out on a Bruker APEXII system equipped with graphite-monochromated Mo Kα radiation (0.71073 Å). A nitrogen-flow Oxford Cryostream-700 was used to control the temperature. Data collections were carried out in the order 100, 150, 200, 250, and 300 K on the same crystal. Data reduction and cell refinement were performed using SAINT and the APEX3 suite (Bruker, 2016). The structure was solved with SHELXT (Sheldrick, 2015a) and an absorption correction was performed with SADABS (Sheldrick, 1999). Structure refinements against F² were carried out using the SHELXL refinement package in APEX3 (Bruker, 2016). The apparent space group for the structure at all five temperatures was suggested to be orthorhombic Pca2₁ by XPREP, which differs from that previously described (i.e. monoclinic, P2/c (Krebs, 1970). The refinement yielded R factors varying from 0.0345 at 100 K to 0.0534 at 300 K.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Zr1	0.4239 (2)	0.3354 (2)	0.5000 (3)	0.0356 (5)
Cl1	0.5702 (8)	0.1380 (7)	0.6280 (4)	0.0515 (15)
Cl2	0.0942 (7)	0.3905 (7)	0.6127 (4)	0.0391 (12)
Cl3	0.2829 (9)	0.1339 (7)	0.3731 (5)	0.0536 (14)
Cl4	0.7504 (7)	0.3930 (6)	0.3853 (4)	0.0407 (12)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Zr1	0.0273 (8)	0.0381 (9)	0.0413 (10)	0.0009 (8)	0.0001 (10)	0.0002 (12)
Cl1	0.047 (3)	0.054 (3)	0.053 (4)	0.006 (3)	−0.005 (3)	0.011 (3)
Cl2	0.032 (3)	0.046 (3)	0.040 (3)	0.004 (2)	0.004 (2)	0.007 (2)
Cl3	0.054 (3)	0.050 (3)	0.056 (3)	−0.006 (3)	−0.004 (3)	−0.009 (3)
Cl4	0.033 (2)	0.046 (3)	0.043 (3)	−0.004 (2)	0.007 (2)	−0.007 (2)

Geometric parameters (Å, º)

Zr1—Cl3	2.310 (6)	Zr1—Cl2^i	2.664 (5)
Zr1—Cl1	2.313 (6)	Zr1—Cl4^ii	2.670 (5)
Zr1—Cl4	2.504 (6)	Cl2—Zr1^ii	2.664 (5)
Zr1—Cl2	2.504 (6)	Cl4—Zr1^i	2.670 (5)
Cl3—Zr1—Cl1	100.6 (2)	Cl2—Zr1—Cl2^i	85.99 (17)
Cl3—Zr1—Cl4	93.3 (2)	Cl3—Zr1—Cl4^ii	89.4 (2)
Cl1—Zr1—Cl4	98.73 (19)	Cl1—Zr1—Cl4^ii	169.0 (2)
Cl3—Zr1—Cl2	98.5 (2)	Cl4—Zr1—Cl4^ii	85.34 (17)
Cl1—Zr1—Cl2	93.9 (2)	Cl2—Zr1—Cl4^ii	79.76 (16)
Cl4—Zr1—Cl2	160.82 (17)	Cl2^i—Zr1—Cl4^ii	81.54 (17)
Cl3—Zr1—Cl2^i	169.0 (2)	Zr1—Cl2—Zr1^ii	100.26 (19)
Cl1—Zr1—Cl2^i	89.0 (2)	Zr1—Cl4—Zr1^i	100.08 (19)
Cl4—Zr1—Cl2^i	79.89 (16)

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

Lattice parameters of ZrCl₄ as measured at the given temperatures

	300 K	250 K	200 K	150 K	100 K
a (Å)	6.262 (9)	6.253 (5)	6.2389 (8)	6.2311 (8)	6.2199 (9)
b (Å)	7.402 (11)	7.383 (6)	7.3667 (10)	7.3497 (10)	7.3301 (10)
c (Å)	12.039 (17)	12.017 (9)	11.9735 (16)	11.9462 (15)	11.9153 (16)
α = β = γ (°)	90	90	90	90	90
V (Å^3)	558.0 (14)	554.8 (7)	550.30 (13)	547.10 (12)	543.25 (13)
Z	4	4	4	4	4
R factor	5.33%	3.82%	3.76%	3.34%	3.45%