Buy article online - an online subscription or single-article purchase is required to access this article.
Ytterbium selenide, Yb2Se3, was prepared by reacting the elements at 1173 K in an evacuated silica tube in an Sn flux. The ytterbium sesquiselenide crystallizes in the orthorhombic space group Fddd, adopting the Sc2S3 structure type. Its structure consists of edge-sharing (slightly distorted) YbSe6 octahedra, and may be regarded as a defect NaCl structure.
Supporting information
Key indicators
- Single-crystal X-ray study
- T = 298 K
- Mean (Yb-Se) = 0.001 Å
- R factor = 0.033
- wR factor = 0.074
- Data-to-parameter ratio = 45.3
checkCIF results
No syntax errors found
ADDSYM reports no extra symmetry
Yb2Se3 was obtained from a reaction of elemental ytterbium and selenium in a tin flux. The mixture was annealed at 1173 K over a period of 4 d, and then slowly cooled (3 K h−1) to room temperature. Yb2Se3 crystallized in the form of black block-shaped crystals.
Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997).
Crystal data top
Yb2Se3 | F(000) = 3872 |
Mr = 582.96 | Dx = 7.152 Mg m−3 |
Orthorhombic, Fddd | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -F 2uv 2vw | Cell parameters from 5337 reflections |
a = 8.0183 (7) Å | θ = 3.2–35.0° |
b = 11.272 (1) Å | µ = 54.32 mm−1 |
c = 23.961 (2) Å | T = 298 K |
V = 2165.7 (3) Å3 | Block, black |
Z = 16 | 0.01 × 0.01 × 0.01 mm |
Data collection top
Bruker SMART APEX CCD diffractometer | 1179 independent reflections |
Radiation source: fine-focus sealed tube | 937 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.049 |
ϕ and ω scans | θmax = 35.0°, θmin = 3.2° |
Absorption correction: ψ scan (SAINT; Bruker, 1999) | h = −12→12 |
Tmin = 0.487, Tmax = 0.581 | k = −17→17 |
5337 measured reflections | l = −32→38 |
Refinement top
Refinement on F2 | Primary atom site location: isomorphous structure methods |
Least-squares matrix: full | w = 1/[σ2(Fo2) + (0.0244P)2] where P = (Fo2 + 2Fc2)/3 |
R[F2 > 2σ(F2)] = 0.033 | (Δ/σ)max = 0.001 |
wR(F2) = 0.074 | Δρmax = 1.70 e Å−3 |
S = 1.12 | Δρmin = −3.52 e Å−3 |
1179 reflections | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
26 parameters | Extinction coefficient: 0.000397 (11) |
0 restraints | |
Crystal data top
Yb2Se3 | V = 2165.7 (3) Å3 |
Mr = 582.96 | Z = 16 |
Orthorhombic, Fddd | Mo Kα radiation |
a = 8.0183 (7) Å | µ = 54.32 mm−1 |
b = 11.272 (1) Å | T = 298 K |
c = 23.961 (2) Å | 0.01 × 0.01 × 0.01 mm |
Data collection top
Bruker SMART APEX CCD diffractometer | 1179 independent reflections |
Absorption correction: ψ scan (SAINT; Bruker, 1999) | 937 reflections with I > 2σ(I) |
Tmin = 0.487, Tmax = 0.581 | Rint = 0.049 |
5337 measured reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.033 | 26 parameters |
wR(F2) = 0.074 | 0 restraints |
S = 1.12 | Δρmax = 1.70 e Å−3 |
1179 reflections | Δρmin = −3.52 e Å−3 |
Special details top
Experimental. The absorption correction was performed using the SAINT package (Bruker, 1999b); the routine is called SADABS. |
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 (Å2) top | x | y | z | Uiso*/Ueq | |
Yb1 | 0.1250 | 0.1250 | 0.041383 (14) | 0.00754 (10) | |
Yb2 | 0.1250 | 0.1250 | 0.377464 (14) | 0.00745 (10) | |
Se1 | 0.37062 (10) | 0.1250 | 0.1250 | 0.00751 (16) | |
Se2 | 0.38115 (7) | 0.12282 (5) | 0.45668 (2) | 0.00758 (13) | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
Yb1 | 0.00865 (17) | 0.00734 (17) | 0.00664 (17) | −0.00092 (14) | 0.000 | 0.000 |
Yb2 | 0.00657 (16) | 0.00766 (17) | 0.00813 (17) | 0.00168 (11) | 0.000 | 0.000 |
Se1 | 0.0078 (4) | 0.0058 (3) | 0.0090 (4) | 0.000 | 0.000 | 0.0001 (3) |
Se2 | 0.0068 (3) | 0.0085 (3) | 0.0074 (3) | −0.0029 (3) | −0.00142 (17) | 0.00012 (19) |
Geometric parameters (Å, º) top
Yb1—Se2i | 2.7943 (6) | Yb2—Se2vii | 2.8086 (7) |
Yb1—Se2ii | 2.7943 (6) | Yb2—Se1i | 2.8188 (3) |
Yb1—Se1 | 2.8095 (6) | Yb2—Se1ii | 2.8188 (2) |
Yb1—Se1iii | 2.8095 (6) | Se1—Yb1viii | 2.8095 (6) |
Yb1—Se2iv | 2.8184 (6) | Se1—Yb2i | 2.8188 (3) |
Yb1—Se2v | 2.8184 (6) | Se1—Yb2ix | 2.8188 (2) |
Yb2—Se2 | 2.7967 (6) | Se2—Yb1i | 2.7943 (6) |
Yb2—Se2iii | 2.7967 (6) | Se2—Yb2vii | 2.8086 (6) |
Yb2—Se2vi | 2.8086 (7) | Se2—Yb1x | 2.8184 (6) |
| | | |
Se2i—Yb1—Se2ii | 178.09 (3) | Se2—Yb2—Se2iii | 94.52 (3) |
Se2i—Yb1—Se1 | 90.028 (12) | Se2—Yb2—Se2vi | 176.864 (19) |
Se2ii—Yb1—Se1 | 88.610 (13) | Se2iii—Yb2—Se2vi | 88.614 (17) |
Se2i—Yb1—Se1iii | 88.610 (13) | Se2—Yb2—Se2vii | 88.614 (17) |
Se2ii—Yb1—Se1iii | 90.028 (12) | Se2iii—Yb2—Se2vii | 176.864 (19) |
Se1—Yb1—Se1iii | 89.02 (3) | Se2vi—Yb2—Se2vii | 88.25 (2) |
Se2i—Yb1—Se2iv | 89.486 (17) | Se2—Yb2—Se1i | 89.788 (17) |
Se2ii—Yb1—Se2iv | 91.888 (18) | Se2iii—Yb2—Se1i | 91.841 (17) |
Se1—Yb1—Se2iv | 179.236 (16) | Se2vi—Yb2—Se1i | 90.136 (17) |
Se1iii—Yb1—Se2iv | 91.562 (18) | Se2vii—Yb2—Se1i | 88.141 (17) |
Se2i—Yb1—Se2v | 91.888 (18) | Se2—Yb2—Se1ii | 91.841 (17) |
Se2ii—Yb1—Se2v | 89.486 (17) | Se2iii—Yb2—Se1ii | 89.788 (17) |
Se1—Yb1—Se2v | 91.562 (18) | Se2vi—Yb2—Se1ii | 88.141 (17) |
Se1iii—Yb1—Se2v | 179.236 (16) | Se2vii—Yb2—Se1ii | 90.136 (17) |
Se2iv—Yb1—Se2v | 87.86 (3) | Se1i—Yb2—Se1ii | 177.600 (14) |
Symmetry codes: (i) −x+1/2, −y, −z+1/2; (ii) x−1/4, y+1/4, −z+1/2; (iii) −x+1/4, −y+1/4, z; (iv) x−1/2, y, z−1/2; (v) −x+3/4, −y+1/4, z−1/2; (vi) x−1/2, −y+1/4, −z+3/4; (vii) −x+3/4, y, −z+3/4; (viii) −x+1/4, y, −z+1/4; (ix) x+1/4, −y+1/2, z−1/4; (x) x+1/2, y, z+1/2. |
Experimental details
Crystal data |
Chemical formula | Yb2Se3 |
Mr | 582.96 |
Crystal system, space group | Orthorhombic, Fddd |
Temperature (K) | 298 |
a, b, c (Å) | 8.0183 (7), 11.272 (1), 23.961 (2) |
V (Å3) | 2165.7 (3) |
Z | 16 |
Radiation type | Mo Kα |
µ (mm−1) | 54.32 |
Crystal size (mm) | 0.01 × 0.01 × 0.01 |
|
Data collection |
Diffractometer | Bruker SMART APEX CCD diffractometer |
Absorption correction | ψ scan (SAINT; Bruker, 1999) |
Tmin, Tmax | 0.487, 0.581 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 5337, 1179, 937 |
Rint | 0.049 |
(sin θ/λ)max (Å−1) | 0.807 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.033, 0.074, 1.12 |
No. of reflections | 1179 |
No. of parameters | 26 |
Δρmax, Δρmin (e Å−3) | 1.70, −3.52 |
Selected bond lengths (Å) topYb1—Se2i | 2.7943 (6) | Yb2—Se2 | 2.7967 (6) |
Yb1—Se2ii | 2.7943 (6) | Yb2—Se2iii | 2.7967 (6) |
Yb1—Se1 | 2.8095 (6) | Yb2—Se2vi | 2.8086 (7) |
Yb1—Se1iii | 2.8095 (6) | Yb2—Se2vii | 2.8086 (7) |
Yb1—Se2iv | 2.8184 (6) | Yb2—Se1i | 2.8188 (3) |
Yb1—Se2v | 2.8184 (6) | Yb2—Se1ii | 2.8188 (2) |
Symmetry codes: (i) −x+1/2, −y, −z+1/2; (ii) x−1/4, y+1/4, −z+1/2; (iii) −x+1/4, −y+1/4, z; (iv) x−1/2, y, z−1/2; (v) −x+3/4, −y+1/4, z−1/2; (vi) x−1/2, −y+1/4, −z+3/4; (vii) −x+3/4, y, −z+3/4. |
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.
The sesquichalcogenides of the rare earth elements adopt different structure types. While the La–Gd chalcogenides crystallize in defect variants of the Th3P4 type (Mauricot et al., 1995), Yb2S3 adopts the α-Al2O3 structure (El Fadli et al., 1994). Based on powder diffractograms, the Sc, Y and Dy–Yb selenides (Dismukes & White, 1965; Flahaut et al., 1965) were reported to form the Sc2S3 structure (Tremblet et al., 1963). The cell dimensions for Yb2Se3 (orthorhombic system) were determined by Dismukes & White (1965) to be a = 11.274 Å, b = 8.021 Å, c = 23.98 Å and V = 2168.5 Å, and by Flahaut et al. (1965) to be a = 11.27 Å, b = 8.02 Å, c = 23.96 Å and V = 2165.6 Å. The atomic positions of Yb2Se3 were not refined in either case; Flahaut et al. (1965) merely extrapolated them from the ideal NaCl structure type. Our single-crystal structure study on Yb2Se3 confirms the suggested Sc2S3 type, and delivers crystallographic details with high accuracy. It is evident that the shifts from the NaCl structure are significant; e.g. the x parameters of Se1 and Se2 are not 3/8 = 0.375, but 0.37062 (10) for Se1 and 0.38115 (7) for Se2. This is reflected in deviations from the ideal Se—Yb—Se bond angles of up to 4.5° and Yb—Se bond lengths varying from 2.7943 (6) to 2.8184 (6) Å (Yb1) and from 2.7967 (6) to 2.8188 (3) Å (Yb2).