inorganic compounds
The β-polymorph of uranium phosphide selenide
aDepartment of Chemistry, Northwestern University, 2145 Sheridan Rd., Evanston, IL 60208-3113, USA
*Correspondence e-mail: ibers@chem.northwestern.edu
β-UPSe was synthesized from the reaction of U2Se3, P and Se in a CsCl in a fused-silica tube. It crystallizes with four formula units in the tetragonal I4/mmm in the UGeTe structure type. The comprises one U (site symmetry 4mm), one Se (4mm), and one P (mmm.) atom. The U atom is coordinated in a monocapped square-antiprismatic arrangement, where the square face is formed by P atoms and the other five vertices are Se atoms. The P site is disordered about a mirror plane, showing half-ocupancy for each of the two resulting P atoms. The title structure is related to that of α-UPSe, which crystallizes with two formula units in the tetragonal P4/nmm in the PbFCl structure type.
Related literature
Whereas β-UPSe crystallizes in the UGeTe structure type (Haneveld & Jellinek, 1969), α-UPSe (Hulliger, 1968; Zygmunt et al., 1974a) crystallizes in the PbFCl structure type (Nieuwenkamp & Bijvoet, 1932). Isostructural compounds UTQ have been synthesized (T = P–Bi, Q = Se–Te) (Hulliger, 1968; Leciejewicz & Zygmunt, 1972; Haneveld & Jellinek, 1969; Zygmunt et al., 1974a,b; Pietraszko & Lukaszewicz, 1975; Pearson, 1985). Magnetic studies have been performed on single crystals of β-UPSe synthesized by the vapor-transport method (Kaczorowski et al., 1995), and other compounds with formula UTQ (Troc, 1987). For synthetic details, see: Bugaris & Ibers (2008) and Haneveld & Jellinek (1969). For standardization of structural data, see: Gelato & Parthé (1987).
Experimental
Crystal data
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Data collection: APEX2 (Bruker, 2009); cell SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008b); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008b); molecular graphics: CrystalMaker (Palmer, 2009); software used to prepare material for publication: SHELXL97.
Supporting information
https://doi.org/10.1107/S1600536811049592/wm2560sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536811049592/wm2560Isup2.hkl
U filings (Oak Ridge National Laboratory) were powdered as previously described (Bugaris & Ibers, 2008; Haneveld & Jellinek, 1969), and U2Se3 was synthesized by the stoichiometric reaction of U and Se (Cerac 99.999%) in a fused-silica tube at 1273 K. Black square plates of β-UPSe were synthesized in the reaction of U2Se3 (0.215 mmol), red P (Aldrich 99%, 0.064 mmol), Se (0.215 mmol), and CsCl (MP Biomedical 99.9%, 1.21 mmol) in a carbon-coated fused-silica tube. Reagents were loaded in an argon-filled and the tube was flame-sealed under 10—4 Torr vacuum. The tube was placed in a computer-controlled furnace and heated to 1273 K in 96 h, held there for 4 h, cooled to 1223 K in 12 h, held there for 96 h, and then cooled to 298 K in 350 h. The solidified was washed off with water. Qualitative EDS analysis using a Hitachi S-3400 SEM showed the presence of U, P, and Se, with no detectable Cs or Cl content in the crystals.
The structure was standardized with the use of STRUCTURE TIDY (Gelato & Parthé, 1987). The highest peak in the difference
is 1.9 (6) e/Å3, 0.03 Å from atom U1, and the deepest hole is -4.8 (6) e/Å3, 0.91 Å from atom U1.The
results in the placement of a half-occupied P1 atom in the 8j position. The resultant disorder at +x,1/2,0 (P1a) and -x,1/2,0 (P1b) leads to impossible P1a–P1b distances of 0.52 Å and 2.42 Å. The P1 atoms are arranged in a square net 2.813 Å on a side. The distribution of P1a squares and P1b squares within a structure is random, as no reflections were observed.The compounds UTQ (T = P, As, As, Bi; Q = S, Se, Te) crystallize in one of two structure types. UBiTe, UTQ (T = As, Sb; Q = S, Se, Te), and UPQ (Q = S, Se) (Hulliger, 1968; Leciejewicz & Zygmunt, 1972; Haneveld & Jellinek, 1969; Zygmunt et al., 1974a; Pietraszko & Lukaszewicz, 1975; Pearson, 1985) crystallize in the tetragonal β-UPSe crystallizing in the UGeTe structure type, but no structural data were reported. β-UPSe orders antiferromagnetically at low temperature (Troc, 1987; Kaczorowski et al., 1995).
P4/nmm in the PbFCl (Nieuwenkamp & Bijvoet, 1932) structure type. UPTe and UAsTe (Pietraszko & Lukaszewicz, 1975; Pearson, 1985; Zygmunt et al., 1974b) crystallize in the tetragonal I4/mmm in the UGeTe (Haneveld & Jellinek, 1969) structure type. Magnetic studies have been performed on single crystals ofWe have synthesized β-UPSe from a CsCl in contrast to previous reported synthetic methods. This compound crystallizes with four formula units in the tetragonal I4/mmm (Figure 1) in the UGeTe structure type. The comprises atoms U1 (site symmetry 4mm), Se1 (4mm), and P1 (mmm.) (Figure 2). U is coordinated in a monocapped square-antiprismatic arrangement, where the square face is formed by P atoms and the other five vertices are Se atoms. These moieties face-share along the four triangular faces formed by two Se atoms and one P atom with adjacent moieties. They also face-share along the square faces formed by P atoms. Finally, each of the four edges on the cap are shared with another moiety so that the U atoms are staggered when viewed down [001]. Viewed on the side of the basal plane, each atom type lies on its own plane.
The structure is related to that of α-UPSe (Zygmunt et al., 1974a; Hulliger, 1968). The only difference is that instead of face-sharing along the square faces formed by the P atoms, the moieties edge-share with four other moieties, such that the U atoms are staggered in a checkerboard pattern when viewed down [001].
Interatomic distances are typical. The U–P distance is 2.8514 (7) Å, comparable to 2.91 Å in α-UPSe (Zygmunt et al., 1974a). The U–Se distances are 2.9605 (5) Å and 3.0633 (11) Å, compared to 2.901 Å and 3.131 Å in α-UPSe.
Whereas β-UPSe crystallizes in the UGeTe structure type (Haneveld & Jellinek, 1969), α-UPSe (Hulliger, 1968; Zygmunt et al., 1974a) crystallizes in the PbFCl structure type (Nieuwenkamp & Bijvoet, 1932). Isostructural compounds UTQ have been synthesized (T = P – Bi, Q = Se – Te) (Hulliger, 1968; Leciejewicz & Zygmunt, 1972; Haneveld & Jellinek, 1969; Zygmunt et al., 1974a,b; Pietraszko & Lukaszewicz, 1975; Pearson, 1985). Magnetic studies have been performed on single crystals of β-UPSe synthesized by the vapor-transport method (Kaczorowski et al., 1995), and other compounds with formula UTQ (Troc, 1987). For synthetic details, see: Bugaris & Ibers (2008) and Haneveld & Jellinek (1969). For standardization of structural data, see: Gelato & Parthé (1987).
Data collection: APEX2 (Bruker, 2009); cell
SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008a); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008a); molecular graphics: CrystalMaker (Palmer, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008a).UPSe | Dx = 9.123 Mg m−3 |
Mr = 347.96 | Mo Kα radiation, λ = 0.71073 Å |
Tetragonal, I4/mmm | Cell parameters from 1519 reflections |
Hall symbol: -I 4 2 | θ = 5.0–28.4° |
a = 3.9443 (4) Å | µ = 78.66 mm−1 |
c = 16.2836 (17) Å | T = 298 K |
V = 253.33 (4) Å3 | Square plate, black |
Z = 4 | 0.41 × 0.39 × 0.03 mm |
F(000) = 564 |
Bruker APEXII CCD diffractometer | 128 independent reflections |
Radiation source: fine-focus sealed tube | 128 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.034 |
φ and ω scans | θmax = 28.4°, θmin = 2.5° |
Absorption correction: numerical face-indexed (SADABS; Sheldrick, 2008b) | h = −5→5 |
Tmin = 0.013, Tmax = 0.175 | k = −5→5 |
1506 measured reflections | l = −21→21 |
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)] = 0.024 | [1.00000 + 0.00000exp(0.00(sinθ/λ)2)]/ [σ2(Fo2) + 0.0000 + 0.0000*P + (0.0377P)2 + 0.0000sinθ/λ] where P = 1.00000Fo2 + 0.00000Fc2 |
wR(F2) = 0.052 | (Δ/σ)max < 0.001 |
S = 1.31 | Δρmax = 1.89 e Å−3 |
128 reflections | Δρmin = −4.77 e Å−3 |
12 parameters | Extinction correction: SHELXL97 (Sheldrick, 2008a), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
0 restraints | Extinction coefficient: 0.0139 (12) |
UPSe | Z = 4 |
Mr = 347.96 | Mo Kα radiation |
Tetragonal, I4/mmm | µ = 78.66 mm−1 |
a = 3.9443 (4) Å | T = 298 K |
c = 16.2836 (17) Å | 0.41 × 0.39 × 0.03 mm |
V = 253.33 (4) Å3 |
Bruker APEXII CCD diffractometer | 128 independent reflections |
Absorption correction: numerical face-indexed (SADABS; Sheldrick, 2008b) | 128 reflections with I > 2σ(I) |
Tmin = 0.013, Tmax = 0.175 | Rint = 0.034 |
1506 measured reflections |
R[F2 > 2σ(F2)] = 0.024 | 12 parameters |
wR(F2) = 0.052 | 0 restraints |
S = 1.31 | Δρmax = 1.89 e Å−3 |
128 reflections | Δρmin = −4.77 e Å−3 |
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. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
U1 | 0.0000 | 0.0000 | 0.125455 (18) | 0.0090 (3) | |
Se1 | 0.0000 | 0.0000 | 0.31358 (6) | 0.0093 (4) | |
P1 | 0.0660 (18) | 0.5000 | 0.0000 | 0.021 (2) | 0.50 |
U11 | U22 | U33 | U12 | U13 | U23 | |
U1 | 0.0066 (3) | 0.0066 (3) | 0.0138 (4) | 0.000 | 0.000 | 0.000 |
Se1 | 0.0068 (4) | 0.0068 (4) | 0.0142 (6) | 0.000 | 0.000 | 0.000 |
P1 | 0.040 (7) | 0.0114 (18) | 0.0107 (13) | 0.000 | 0.000 | 0.000 |
U1—P1i | 2.8514 (7) | U1—U1iv | 3.9443 (4) |
U1—P1ii | 2.8514 (7) | U1—U1ii | 4.0858 (7) |
U1—P1iii | 2.8514 (7) | P1—P1vii | 0.520 (14) |
U1—P1iv | 2.8514 (7) | P1—P1xv | 2.421 (10) |
U1—P1v | 2.8514 (7) | P1—P1vi | 2.421 (10) |
U1—P1vi | 2.8514 (7) | P1—P1xvi | 2.8132 (13) |
U1—P1vii | 2.8514 (7) | P1—P1iii | 2.8132 (13) |
U1—P1 | 2.8514 (7) | P1—P1xvii | 2.8132 (13) |
U1—Se1viii | 2.9605 (5) | P1—P1v | 2.8132 (13) |
U1—Se1ix | 2.9605 (5) | P1—U1ii | 2.8514 (7) |
U1—Se1x | 2.9605 (5) | P1—U1xiv | 2.8514 (7) |
U1—Se1xi | 2.9605 (5) | P1—U1vii | 2.8514 (7) |
U1—Se1 | 3.0633 (11) | P1—P1i | 3.157 (10) |
U1—U1xii | 3.9443 (4) | P1—P1xviii | 3.157 (10) |
U1—U1xiii | 3.9443 (4) | P1—P1xix | 3.424 (14) |
U1—U1xiv | 3.9443 (4) | ||
P1i—U1—P1ii | 50.2 (2) | P1iii—U1—Se1xi | 139.62 (13) |
P1ii—U1—P1iii | 59.116 (17) | P1iv—U1—Se1xi | 73.66 (10) |
P1i—U1—P1iv | 59.116 (17) | P1v—U1—Se1xi | 73.66 (10) |
P1iii—U1—P1iv | 67.2 (2) | P1vi—U1—Se1xi | 80.81 (10) |
P1i—U1—P1v | 87.52 (3) | P1vii—U1—Se1xi | 139.62 (13) |
P1ii—U1—P1v | 59.116 (17) | P1—U1—Se1xi | 129.81 (13) |
P1iii—U1—P1v | 88.48 (3) | Se1viii—U1—Se1xi | 83.543 (13) |
P1iv—U1—P1v | 50.2 (2) | Se1ix—U1—Se1xi | 83.543 (13) |
P1i—U1—P1vi | 88.48 (3) | Se1x—U1—Se1xi | 140.81 (4) |
P1ii—U1—P1vi | 67.2 (2) | P1i—U1—Se1 | 135.762 (15) |
P1iii—U1—P1vi | 87.52 (3) | P1ii—U1—Se1 | 135.762 (15) |
P1iv—U1—P1vi | 59.116 (17) | P1iii—U1—Se1 | 135.762 (15) |
P1i—U1—P1vii | 59.116 (17) | P1iv—U1—Se1 | 135.762 (15) |
P1ii—U1—P1vii | 87.52 (3) | P1v—U1—Se1 | 135.762 (15) |
P1iii—U1—P1vii | 50.2 (2) | P1vi—U1—Se1 | 135.762 (15) |
P1iv—U1—P1vii | 88.48 (3) | P1vii—U1—Se1 | 135.762 (15) |
P1v—U1—P1vii | 67.2 (2) | P1—U1—Se1 | 135.762 (15) |
P1vi—U1—P1vii | 59.116 (17) | Se1viii—U1—Se1 | 70.41 (2) |
P1i—U1—P1 | 67.2 (2) | Se1ix—U1—Se1 | 70.41 (2) |
P1ii—U1—P1 | 88.48 (3) | Se1x—U1—Se1 | 70.41 (2) |
P1iii—U1—P1 | 59.116 (17) | Se1xi—U1—Se1 | 70.41 (2) |
P1iv—U1—P1 | 87.52 (3) | P1i—U1—P1xx | 47.14 (19) |
P1v—U1—P1 | 59.116 (17) | P1ii—U1—P1xx | 25.69 (12) |
P1vi—U1—P1 | 50.2 (2) | P1iii—U1—P1xx | 57.61 (9) |
P1i—U1—Se1viii | 139.62 (13) | P1iv—U1—P1xx | 34.53 (13) |
P1ii—U1—Se1viii | 139.62 (13) | P1v—U1—P1xx | 84.63 (11) |
P1iii—U1—Se1viii | 129.81 (13) | P1vi—U1—P1xx | 92.92 (11) |
P1iv—U1—Se1viii | 129.81 (13) | P1vii—U1—P1xx | 101.21 (11) |
P1v—U1—Se1viii | 80.81 (10) | P1—U1—P1xx | 105.774 (19) |
P1vi—U1—Se1viii | 73.66 (10) | Se1viii—U1—P1xx | 163.21 (3) |
P1vii—U1—Se1viii | 80.81 (10) | Se1ix—U1—P1xx | 48.49 (3) |
P1—U1—Se1viii | 73.66 (10) | Se1x—U1—P1xx | 113.11 (3) |
P1i—U1—Se1ix | 73.66 (10) | Se1xi—U1—P1xx | 84.38 (5) |
P1ii—U1—Se1ix | 73.66 (10) | Se1—U1—P1xx | 116.05 (3) |
P1iii—U1—Se1ix | 80.81 (10) | Se1viii—U1—P1xxi | 163.21 (3) |
P1iv—U1—Se1ix | 80.81 (10) | Se1ix—U1—P1xxi | 48.49 (2) |
P1v—U1—Se1ix | 129.81 (13) | Se1x—U1—P1xxi | 84.38 (5) |
P1vi—U1—Se1ix | 139.62 (13) | Se1xi—U1—P1xxi | 113.11 (3) |
P1vii—U1—Se1ix | 129.81 (13) | Se1—U1—P1xxi | 116.05 (3) |
P1—U1—Se1ix | 139.62 (13) | U1viii—Se1—U1ix | 140.82 (4) |
Se1viii—U1—Se1ix | 140.81 (4) | U1viii—Se1—U1x | 83.544 (13) |
P1i—U1—Se1x | 80.81 (10) | U1ix—Se1—U1x | 83.544 (13) |
P1ii—U1—Se1x | 129.81 (13) | U1viii—Se1—U1xi | 83.544 (13) |
P1iii—U1—Se1x | 73.66 (10) | U1ix—Se1—U1xi | 83.544 (13) |
P1iv—U1—Se1x | 139.62 (13) | U1x—Se1—U1xi | 140.82 (4) |
P1v—U1—Se1x | 139.62 (13) | U1viii—Se1—U1 | 109.59 (2) |
P1vi—U1—Se1x | 129.81 (13) | U1ix—Se1—U1 | 109.59 (2) |
P1vii—U1—Se1x | 73.66 (10) | U1x—Se1—U1 | 109.59 (2) |
P1—U1—Se1x | 80.81 (10) | U1xi—Se1—U1 | 109.59 (2) |
Se1viii—U1—Se1x | 83.543 (13) | U1xxii—P1—U1xxiii | 176.41 (10) |
Se1ix—U1—Se1x | 83.543 (13) | U1xii—P1—U1xxiii | 131.945 (10) |
P1i—U1—Se1xi | 129.81 (13) | U1xix—P1—U1xxiii | 130.116 (13) |
P1ii—U1—Se1xi | 80.81 (10) | U1xxiv—P1—U1xxiii | 108.344 (10) |
Symmetry codes: (i) y−1, −x, −z; (ii) −x, −y, −z; (iii) −y, x, z; (iv) x, y−1, z; (v) y, −x, −z; (vi) −y+1, x, z; (vii) −x, −y+1, −z; (viii) −x+1/2, −y+1/2, −z+1/2; (ix) −x−1/2, −y−1/2, −z+1/2; (x) −x−1/2, −y+1/2, −z+1/2; (xi) −x+1/2, −y−1/2, −z+1/2; (xii) x+1, y, z; (xiii) x−1, y, z; (xiv) x, y+1, z; (xv) y, −x+1, −z; (xvi) −y+1, x+1, z; (xvii) y−1, −x+1, −z; (xviii) −y, x+1, z; (xix) −x+1, −y+1, −z; (xx) −y, x−1, z; (xxi) x−1, y−1, z; (xxii) x+1, y+1, z; (xxiii) −x−1, −y, −z; (xxiv) −x+1, −y, −z. |
Experimental details
Crystal data | |
Chemical formula | UPSe |
Mr | 347.96 |
Crystal system, space group | Tetragonal, I4/mmm |
Temperature (K) | 298 |
a, c (Å) | 3.9443 (4), 16.2836 (17) |
V (Å3) | 253.33 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 78.66 |
Crystal size (mm) | 0.41 × 0.39 × 0.03 |
Data collection | |
Diffractometer | Bruker APEXII CCD |
Absorption correction | Numerical face-indexed (SADABS; Sheldrick, 2008b) |
Tmin, Tmax | 0.013, 0.175 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 1506, 128, 128 |
Rint | 0.034 |
(sin θ/λ)max (Å−1) | 0.669 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.024, 0.052, 1.31 |
No. of reflections | 128 |
No. of parameters | 12 |
Δρmax, Δρmin (e Å−3) | 1.89, −4.77 |
Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008a), SHELXL97 (Sheldrick, 2008a), CrystalMaker (Palmer, 2009).
Acknowledgements
Funding for this research was kindly provided by the US Department of Energy, Basic Energy Sciences, Chemical Sciences, Biosciences, and Geosciences Division and Division of Materials Science and Engineering grant ER–15522. SEM analyses were conducted in the Electron Probe Instrumentation Center (EPIC) at the Northwestern University Atomic and Nanoscale Characterization Experimental (NUANCE) Center, supported by the NSF-NSEC, the NSF-MRSEC, the Keck Foundation, the State of Illinois, and Northwestern University. Single-crystal data were collected at the IMSERC X-ray Facility at Northwestern University, supported by the International Institute of Nanotechnology (IIN).
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The compounds UTQ (T = P, As, As, Bi; Q = S, Se, Te) crystallize in one of two structure types. UBiTe, UTQ (T = As, Sb; Q = S, Se, Te), and UPQ (Q = S, Se) (Hulliger, 1968; Leciejewicz & Zygmunt, 1972; Haneveld & Jellinek, 1969; Zygmunt et al., 1974a; Pietraszko & Lukaszewicz, 1975; Pearson, 1985) crystallize in the tetragonal space group P4/nmm in the PbFCl (Nieuwenkamp & Bijvoet, 1932) structure type. UPTe and UAsTe (Pietraszko & Lukaszewicz, 1975; Pearson, 1985; Zygmunt et al., 1974b) crystallize in the tetragonal space group I4/mmm in the UGeTe (Haneveld & Jellinek, 1969) structure type. Magnetic studies have been performed on single crystals of β-UPSe crystallizing in the UGeTe structure type, but no structural data were reported. β-UPSe orders antiferromagnetically at low temperature (Troc, 1987; Kaczorowski et al., 1995).
We have synthesized β-UPSe from a CsCl flux, in contrast to previous reported synthetic methods. This compound crystallizes with four formula units in the tetragonal space group I4/mmm (Figure 1) in the UGeTe structure type. The asymmetric unit comprises atoms U1 (site symmetry 4mm), Se1 (4mm), and P1 (mmm.) (Figure 2). U is coordinated in a monocapped square-antiprismatic arrangement, where the square face is formed by P atoms and the other five vertices are Se atoms. These moieties face-share along the four triangular faces formed by two Se atoms and one P atom with adjacent moieties. They also face-share along the square faces formed by P atoms. Finally, each of the four edges on the cap are shared with another moiety so that the U atoms are staggered when viewed down [001]. Viewed on the side of the basal plane, each atom type lies on its own plane.
The structure is related to that of α-UPSe (Zygmunt et al., 1974a; Hulliger, 1968). The only difference is that instead of face-sharing along the square faces formed by the P atoms, the moieties edge-share with four other moieties, such that the U atoms are staggered in a checkerboard pattern when viewed down [001].
Interatomic distances are typical. The U–P distance is 2.8514 (7) Å, comparable to 2.91 Å in α-UPSe (Zygmunt et al., 1974a). The U–Se distances are 2.9605 (5) Å and 3.0633 (11) Å, compared to 2.901 Å and 3.131 Å in α-UPSe.