Buy article online - an online subscription or single-article purchase is required to access this article.
Download citation
Download citation
link to html
Zirconium germanium tetra­telluride, ZrGeTe4, is isostructural with Hf0.85GeTe4 [Mar & Ibers (1993). J. Am Chem. Soc. 115, 3227-3238], but the Zr site in ZrGeTe4 is fully occupied and the compound is stoichiometric. ZrGeTe4 adopts a layered structural type. Each layer is composed of two unique one-dimensional chains of face-sharing Zr-centered bicapped trigonal prisms and corner-sharing Ge-centered tetra­hedra.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807045862/fi2044sup1.cif
Contains datablocks global, I

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S1600536807045862/fi2044Isup2.hkl
Contains datablock I

Key indicators

  • Single-crystal X-ray study
  • T = 150 K
  • Mean [sigma](r-Ge) = 0.002 Å
  • R factor = 0.036
  • wR factor = 0.080
  • Data-to-parameter ratio = 23.8

checkCIF/PLATON results

No syntax errors found



Alert level G REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is correct. If it is not, please give the correct count in the _publ_section_exptl_refinement section of the submitted CIF. From the CIF: _diffrn_reflns_theta_max 27.46 From the CIF: _reflns_number_total 904 Count of symmetry unique reflns 479 Completeness (_total/calc) 188.73% TEST3: Check Friedels for noncentro structure Estimate of Friedel pairs measured 425 Fraction of Friedel pairs measured 0.887 Are heavy atom types Z>Si present yes PLAT794_ALERT_5_G Check Predicted Bond Valency for Te1 (*) 1.98 PLAT794_ALERT_5_G Check Predicted Bond Valency for Te2 (*) 2.14 PLAT794_ALERT_5_G Check Predicted Bond Valency for Te3 (*) 1.75 PLAT794_ALERT_5_G Check Predicted Bond Valency for Te4 (*) 1.84 PLAT794_ALERT_5_G Check Predicted Bond Valency for Zr (4) 3.04 PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints ....... 1
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 0 ALERT level C = Check and explain 7 ALERT level G = General alerts; check 0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 0 ALERT type 2 Indicator that the structure model may be wrong or deficient 1 ALERT type 3 Indicator that the structure quality may be low 1 ALERT type 4 Improvement, methodology, query or suggestion 5 ALERT type 5 Informative message, check

Comment top

The title compound is isostructural with Hf0.85GeTe4 (Mar & Ibers, 1993). A view of the structure down the a axis in Fig. 1 shows the layered nature of the compound. Fig 2. shows that an individual layer is composed of two unique one-dimensional chains of face-sharing Zr-centered bicapped trigonal prisms and corner-sharing Ge-centered tetrahedra.

The Zr atom is surrounded by six Te atoms in a trigonal prismatic manner, the vertices of two base sides of the prism are composed of six Te atoms. Atoms Te1, Te2, and Te3 form a triangle that is isosceles, the Te1—Te2 distance (2.736 (1) Å) being much shorter than the other two (> 3.0 Å). This short Te1—Te2 separation is typical of (Te—Te)2- pair (Furuseth et al., 1973). Te4 and Ge cap two of the rectangular faces of the trigonal prism to complete the Zr-centered bicapped trigonal prismatic coordination. These trigonal prisms share their triangular faces to form an infinite chain, 1[ZrGeTe4] along the direction of the a axis.

The Ge atom is surrounded by three Te and one Zr atoms in a distorted tetrahedral fashion. These tetrahedra share their corners through the Te4 atom to form an infinite chain. The bicapped trigonal prismatic and the tetrahedral chains are fused through Zr—Ge bonds to form a double chain and finally these chains are connected along the c axis to complete the two-dimensional layer. These layers then stack on top of each other to form the three-dimensional structure with an undulating van der Waals gap shown in Fig. 1.

We have checked many crystals from different reactions with various starting Zr/Te and Hf/Te ratios. We were not able to find nonstoichiometric M0.85GeTe4 (M=Zr, Hf) phases and we believe that the nature of the nonstoichiometry varies depending on the synthetic method.

Related literature top

The synthesis and characterization of Hf0.85GeTe4 have been published (Mar & Ibers, 1993). The Zr analogue of this phase has also been found but detailed structural studies on ZrGeTe4 have not been reported yet. The title compound, ZrGeTe4, is isostructural with Hf0.85GeTe4 except the absolute structure. However, the Zr site in ZrGeTe4 is fully occupied.

For related literature, see: Furuseth et al. (1973).

Experimental top

ZrGeTe4 was obtained from a reaction of Zr(CERAC, 99.7%), Ge(CERAC, 99.999%) and Te(CERAC, 99.95%) in an elemental ratio of 1:1:4 in the presence of KCl as flux. The mass ratio of reactants and flux was 1:2. The starting materials were placed in a fused-silica tube. The tube was evacuated to 10-3 torr, sealed, and heated to 973 K at a rate of 15 K/hr, where it was kept for 72 hrs. The tube was cooled at a rate of 8 K/hr to 373 K and the furnace was shut off. Air- and water-stable metallic shiny needle-shaped crystals were isolated after the flux was removed with water. Qualitative analysis of the crystals with a WDX-equipped scanning electron microscope indicated the presence of Zr, Ge, and Te. No other element was detected.

Refinement top

Although the anisotropic displacement parameters (ADPs) of the Zr atom were comparable to those of the other atoms, the nonstoichiometry of Zr in ZrGeTe4 was checked by refining the occupancy and ADPs of Zr while those of the other atoms were fixed. With the nonstoichiometric model, both parameter were not changed significantly and the residuals (wR2, R1 indices) were remained the same. The highest peak/deepest hole in the Fourier map are found 1.74Å from Te2 and 0.73Å from Te3.

Structure description top

The title compound is isostructural with Hf0.85GeTe4 (Mar & Ibers, 1993). A view of the structure down the a axis in Fig. 1 shows the layered nature of the compound. Fig 2. shows that an individual layer is composed of two unique one-dimensional chains of face-sharing Zr-centered bicapped trigonal prisms and corner-sharing Ge-centered tetrahedra.

The Zr atom is surrounded by six Te atoms in a trigonal prismatic manner, the vertices of two base sides of the prism are composed of six Te atoms. Atoms Te1, Te2, and Te3 form a triangle that is isosceles, the Te1—Te2 distance (2.736 (1) Å) being much shorter than the other two (> 3.0 Å). This short Te1—Te2 separation is typical of (Te—Te)2- pair (Furuseth et al., 1973). Te4 and Ge cap two of the rectangular faces of the trigonal prism to complete the Zr-centered bicapped trigonal prismatic coordination. These trigonal prisms share their triangular faces to form an infinite chain, 1[ZrGeTe4] along the direction of the a axis.

The Ge atom is surrounded by three Te and one Zr atoms in a distorted tetrahedral fashion. These tetrahedra share their corners through the Te4 atom to form an infinite chain. The bicapped trigonal prismatic and the tetrahedral chains are fused through Zr—Ge bonds to form a double chain and finally these chains are connected along the c axis to complete the two-dimensional layer. These layers then stack on top of each other to form the three-dimensional structure with an undulating van der Waals gap shown in Fig. 1.

We have checked many crystals from different reactions with various starting Zr/Te and Hf/Te ratios. We were not able to find nonstoichiometric M0.85GeTe4 (M=Zr, Hf) phases and we believe that the nature of the nonstoichiometry varies depending on the synthetic method.

The synthesis and characterization of Hf0.85GeTe4 have been published (Mar & Ibers, 1993). The Zr analogue of this phase has also been found but detailed structural studies on ZrGeTe4 have not been reported yet. The title compound, ZrGeTe4, is isostructural with Hf0.85GeTe4 except the absolute structure. However, the Zr site in ZrGeTe4 is fully occupied.

For related literature, see: Furuseth et al. (1973).

Computing details top

Data collection: RAPID-AUTO (Rigaku, 2006); cell refinement: RAPID-AUTO (Rigaku, 2006); data reduction: RAPID-AUTO (Rigaku, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: locally modified version of ORTEP (Johnson, 1965); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. View of ZrGeTe4 down the a axis, showing the layered nature of the compound. Filled, grey, and open circles represent Zr, Ge, and Te atoms, respectively. Displacement ellipsoids are drawn at the 90% probability level.
[Figure 2] Fig. 2. View of ZrGeTe4 down the b axis, showing a two-dimensional layer. Atoms are as marked in Fig. 1. [Symmetry code: (i) -1 + x, y, z; (ii) -1/2 - x, 1/2 - y, 1/2 + z; (iii) 1/2 - x, 1/2 - y, 1/2 + z.]
Zirconium germanium tetratelluride top
Crystal data top
ZrGeTe4F(000) = 1120
Mr = 674.24Dx = 6.425 Mg m3
Orthorhombic, Cmc21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: C 2c -2Cell parameters from 3442 reflections
a = 3.9794 (2) Åθ = 3.2–27.5°
b = 15.9296 (10) ŵ = 22.09 mm1
c = 10.9957 (6) ÅT = 150 K
V = 697.02 (7) Å3Needle, metallic silver
Z = 40.50 × 0.03 × 0.02 mm
Data collection top
Rigaku R-AXIS RAPID
diffractometer
899 reflections with I > 2σ(I)
ω scansRint = 0.081
Absorption correction: numerical
(NUMABS; Higashi, 2000)
θmax = 27.5°, θmin = 3.2°
Tmin = 0.482, Tmax = 0.625h = 54
3351 measured reflectionsk = 2020
904 independent reflectionsl = 1314
Refinement top
Refinement on F2 w = 1/[σ2(Fo2) + (0.0268P)2 + 0.122P]
where P = (Fo2 + 2Fc2)/3
Least-squares matrix: full(Δ/σ)max < 0.001
R[F2 > 2σ(F2)] = 0.036Δρmax = 1.40 e Å3
wR(F2) = 0.080Δρmin = 2.31 e Å3
S = 1.07Extinction correction: SHELXL97 (Sheldrick, 1997), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
904 reflectionsExtinction coefficient: 0.0134 (6)
38 parametersAbsolute structure: Flack (1983), 420 Friedel pairs
1 restraintAbsolute structure parameter: 0.01 (3)
Crystal data top
ZrGeTe4V = 697.02 (7) Å3
Mr = 674.24Z = 4
Orthorhombic, Cmc21Mo Kα radiation
a = 3.9794 (2) ŵ = 22.09 mm1
b = 15.9296 (10) ÅT = 150 K
c = 10.9957 (6) Å0.50 × 0.03 × 0.02 mm
Data collection top
Rigaku R-AXIS RAPID
diffractometer
904 independent reflections
Absorption correction: numerical
(NUMABS; Higashi, 2000)
899 reflections with I > 2σ(I)
Tmin = 0.482, Tmax = 0.625Rint = 0.081
3351 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0361 restraint
wR(F2) = 0.080Δρmax = 1.40 e Å3
S = 1.07Δρmin = 2.31 e Å3
904 reflectionsAbsolute structure: Flack (1983), 420 Friedel pairs
38 parametersAbsolute structure parameter: 0.01 (3)
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Zr0.00000.34835 (8)0.77333 (11)0.0065 (3)
Ge0.00000.22779 (8)0.96377 (13)0.0077 (3)
Te10.50000.48455 (5)0.74420 (8)0.0083 (2)
Te20.50000.39999 (5)0.96079 (7)0.0084 (2)
Te30.50000.22096 (6)0.69689 (7)0.0070 (2)
Te40.00000.38129 (5)0.50002 (7)0.0073 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Zr0.0068 (5)0.0086 (6)0.0042 (5)0.0000.0000.0001 (5)
Ge0.0079 (5)0.0108 (7)0.0044 (5)0.0000.0000.0008 (5)
Te10.0089 (3)0.0097 (5)0.0065 (4)0.0000.0000.0001 (3)
Te20.0087 (3)0.0117 (5)0.0048 (4)0.0000.0000.0012 (3)
Te30.0082 (3)0.0087 (4)0.0042 (4)0.0000.0000.0010 (3)
Te40.0071 (3)0.0094 (4)0.0053 (4)0.0000.0000.0006 (3)
Geometric parameters (Å, º) top
Zr—Ge2.8413 (17)Ge—Te4iii2.6716 (10)
Zr—Te12.9612 (11)Ge—Te3iii2.6903 (16)
Zr—Te1i2.9612 (11)Te1—Te22.7361 (12)
Zr—Te3i2.9637 (11)Te1—Zriv2.9612 (11)
Zr—Te32.9637 (11)Te2—Zriv2.9806 (11)
Zr—Te22.9806 (11)Te3—Gev2.6903 (16)
Zr—Te2i2.9806 (11)Te3—Zriv2.9637 (11)
Zr—Te43.0507 (15)Te4—Gevi2.6716 (10)
Ge—Te4ii2.6716 (10)Te4—Gev2.6716 (10)
Ge—Zr—Te1125.10 (4)Te1i—Zr—Te476.55 (4)
Ge—Zr—Te1i125.10 (4)Te3i—Zr—Te480.70 (3)
Te1—Zr—Te1i84.43 (4)Te3—Zr—Te480.70 (3)
Ge—Zr—Te3i75.30 (4)Te2—Zr—Te4129.33 (3)
Te1—Zr—Te3i157.24 (5)Te2i—Zr—Te4129.33 (3)
Te1i—Zr—Te3i91.14 (2)Te4ii—Ge—Te4iii96.28 (5)
Ge—Zr—Te375.30 (4)Te4ii—Ge—Te3iii93.17 (5)
Te1—Zr—Te391.14 (2)Te4iii—Ge—Te3iii93.17 (5)
Te1i—Zr—Te3157.24 (5)Te4ii—Ge—Zr123.34 (4)
Te3i—Zr—Te384.34 (4)Te4iii—Ge—Zr123.34 (4)
Ge—Zr—Te271.15 (3)Te3iii—Ge—Zr119.81 (6)
Te1—Zr—Te254.84 (3)Te2—Te1—Zr62.94 (3)
Te1i—Zr—Te2108.73 (5)Te2—Te1—Zriv62.94 (3)
Te3i—Zr—Te2146.43 (5)Zr—Te1—Zriv84.43 (4)
Te3—Zr—Te286.38 (2)Te1—Te2—Zr62.22 (3)
Ge—Zr—Te2i71.15 (3)Te1—Te2—Zriv62.22 (3)
Te1—Zr—Te2i108.73 (5)Zr—Te2—Zriv83.76 (4)
Te1i—Zr—Te2i54.84 (3)Gev—Te3—Zriv93.58 (4)
Te3i—Zr—Te2i86.38 (2)Gev—Te3—Zr93.58 (4)
Te3—Zr—Te2i146.43 (5)Zriv—Te3—Zr84.34 (4)
Te2—Zr—Te2i83.76 (4)Gevi—Te4—Gev96.28 (5)
Ge—Zr—Te4147.38 (6)Gevi—Te4—Zr92.01 (4)
Te1—Zr—Te476.55 (4)Gev—Te4—Zr92.01 (4)
Symmetry codes: (i) x1, y, z; (ii) x1/2, y+1/2, z+1/2; (iii) x+1/2, y+1/2, z+1/2; (iv) x+1, y, z; (v) x+1/2, y+1/2, z1/2; (vi) x1/2, y+1/2, z1/2.

Experimental details

Crystal data
Chemical formulaZrGeTe4
Mr674.24
Crystal system, space groupOrthorhombic, Cmc21
Temperature (K)150
a, b, c (Å)3.9794 (2), 15.9296 (10), 10.9957 (6)
V3)697.02 (7)
Z4
Radiation typeMo Kα
µ (mm1)22.09
Crystal size (mm)0.50 × 0.03 × 0.02
Data collection
DiffractometerRigaku R-AXIS RAPID
Absorption correctionNumerical
(NUMABS; Higashi, 2000)
Tmin, Tmax0.482, 0.625
No. of measured, independent and
observed [I > 2σ(I)] reflections
3351, 904, 899
Rint0.081
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.036, 0.080, 1.07
No. of reflections904
No. of parameters38
No. of restraints1
Δρmax, Δρmin (e Å3)1.40, 2.31
Absolute structureFlack (1983), 420 Friedel pairs
Absolute structure parameter0.01 (3)

Computer programs: RAPID-AUTO (Rigaku, 2006), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), locally modified version of ORTEP (Johnson, 1965), WinGX (Farrugia, 1999).

Selected geometric parameters (Å, º) top
Zr—Ge2.8413 (17)Zr—Te2i2.9806 (11)
Zr—Te12.9612 (11)Zr—Te43.0507 (15)
Zr—Te1i2.9612 (11)Ge—Te4ii2.6716 (10)
Zr—Te3i2.9637 (11)Ge—Te4iii2.6716 (10)
Zr—Te32.9637 (11)Ge—Te3iii2.6903 (16)
Zr—Te22.9806 (11)Te1—Te22.7361 (12)
Te4ii—Ge—Te4iii96.28 (5)Te4iii—Ge—Zr123.34 (4)
Te4iii—Ge—Te3iii93.17 (5)Te3iii—Ge—Zr119.81 (6)
Symmetry codes: (i) x1, y, z; (ii) x1/2, y+1/2, z+1/2; (iii) x+1/2, y+1/2, z+1/2.
 

Subscribe to Acta Crystallographica Section E: Crystallographic Communications

The full text of this article is available to subscribers to the journal.

If you have already registered and are using a computer listed in your registration details, please email support@iucr.org for assistance.

Buy online

You may purchase this article in PDF and/or HTML formats. For purchasers in the European Community who do not have a VAT number, VAT will be added at the local rate. Payments to the IUCr are handled by WorldPay, who will accept payment by credit card in several currencies. To purchase the article, please complete the form below (fields marked * are required), and then click on `Continue'.
E-mail address* 
Repeat e-mail address* 
(for error checking) 

Format*   PDF (US $40)
   HTML (US $40)
   PDF+HTML (US $50)
In order for VAT to be shown for your country javascript needs to be enabled.

VAT number 
(non-UK EC countries only) 
Country* 
 

Terms and conditions of use
Contact us

Follow Acta Cryst. E
Sign up for e-alerts
Follow Acta Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds