inorganic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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Lutetium(III) cyclo­tetra­phosphate

aLaboratoire de Chimie Industrielle, Département de Génie des Matériaux, Ecole Nationale d'Ingénieurs de Sfax, Université de Sfax, BP W 3038, Sfax, Tunisia, and bLaboratoire des Matériaux Inorganiques, UMR CNRS 6002, Université Blaise Pascal, 24 Avenue des Landais, 63177 Aubière, France
*Correspondence e-mail: daniel.avignant@univ-bpclermont.fr

(Received 28 April 2010; accepted 4 May 2010; online 8 May 2010)

Single crystals of the title compound, tetra­lutetium(III) tris­(cyclo­tetra­phosphate), Lu4(P4O12)3, were obtained by solid-state reaction. The cubic structure is isotypic with its AlIII and ScIII analogues and is built up from four-membered (P4O12)4− phosphate ring anions ([\overline{4}] symmetry), isolated from each other and further linked through isolated LuO6 octa­hedra (.3. symmetry) via corner sharing. Each LuO6 octa­hedron is linked to six (P4O12)4− rings, while each (P4O12)4− ring is linked to eight LuO6 octa­hedra.

Related literature

The title compound belongs to a structural type discovered a long time ago through the Al4(P4O12)3 member, the structure of which was first investigated by Hendricks & Wyckoff (1927[Hendricks, S. B. & Wyckoff, R. W. G. (1927). Am. J. Sci. 13, 491-496.]) and then described by Pauling & Sherman (1937[Pauling, L. & Sherman, J. S. (1937). Z. Kristallogr. 96, 481-487.]). Since then, five isotypic compounds have been characterized: Cr4(P4O12)3 (Rémy & Boullé, 1964[Rémy, P. & Boullé, A. (1964). C. R. Acad. Sci. 258, 927-929.]); Ti4(P4O12)3 (Liebau & Williams, 1964[Liebau, F. & Williams, H. P. (1964). Angew. Chem. 76, 303-304.]); Fe4(P4O12)3 (d'Yvoire et al., 1962[d'Yvoire, F. (1962). Bull. Soc. Chim. pp. 1237-1243.]); Sc4(P4O12)3 (Bagieu-Beucher, 1976[Bagieu-Beucher, M. (1976). J. Appl. Cryst. 9, 368-369.]; Mezentseva et al., 1977[Mezentseva, L. P., Domanskii, A. I. & Bondar, I. A. (1977). Russ. J. Inorg. Chem. 22, 43-45.]; Bagieu-Beucher & Guitel, 1978[Bagieu-Beucher, M. & Guitel, J. C. (1978). Acta Cryst. B34, 1439-1442.]; Smolin et al. 1978[Smolin, Y. I., Shepelev, Y. F., Domanskii, A. I. & Belov, N. V. (1978). Kristallografiya, 23, 187-188.]) and Yb4(P4O12)3 (Chudinova, 1979[Chudinova, N. N. (1979). Izv. Akad. Nauk SSSR Neorg. Mater. 15, 833-837.]). For a review of the crystal chemistry of cyclo­tetra­phosphates, see: Durif (1995[Durif, A. (1995). In Crystal Chemistry of Condensed Phosphates. New York and London: Plenum Press.]). For other polymorphs of composition Lu(PO3)3, see: Höppe & Sedlmaier (2007[Höppe, H. A. & Sedlmaier, S. J. (2007). Inorg. Chem. 46, 3467-3474.]); Yuan et al. (2008[Yuan, J. L., Zhang, H., Zhao, J. T., Chen, H. H., Yang, X. X. & Zhang, G. B. (2008). Opt. Mater. 30, 1369-1374.]); Bejaoui et al. (2008[Bejaoui, A., Horchani-Naifer, K. & Férid, M. (2008). Acta Cryst. E64, i48.]).

Experimental

Crystal data
  • Lu4(P4O12)3

  • Mr = 1647.52

  • Cubic, [I \overline 43d ]

  • a = 14.6920 (6) Å

  • V = 3171.3 (2) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 13.08 mm−1

  • T = 296 K

  • 0.18 × 0.10 × 0.08 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2008[Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.534, Tmax = 0.746

  • 3088 measured reflections

  • 717 independent reflections

  • 659 reflections with I > 2σ(I)

  • Rint = 0.034

Refinement
  • R[F2 > 2σ(F2)] = 0.020

  • wR(F2) = 0.038

  • S = 1.03

  • 717 reflections

  • 41 parameters

  • Δρmax = 0.90 e Å−3

  • Δρmin = −0.67 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 272 Friedel pairs

  • Flack parameter: 0.000 (15)

Table 1
Selected bond lengths (Å)

Lu—O3i 2.182 (3)
Lu—O3ii 2.182 (3)
Lu—O3 2.182 (3)
Lu—O2i 2.185 (4)
Lu—O2ii 2.185 (4)
Lu—O2 2.185 (4)
P—O2iii 1.464 (4)
P—O3 1.481 (4)
P—O1iv 1.583 (3)
P—O1 1.594 (3)
Symmetry codes: (i) [-z+1, x-{\script{1\over 2}}, -y+{\script{1\over 2}}]; (ii) [y+{\script{1\over 2}}, -z+{\script{1\over 2}}, -x+1]; (iii) [-z+1, -x+{\script{3\over 2}}, y]; (iv) [-y+{\script{5\over 4}}, x-{\script{3\over 4}}, -z+{\script{3\over 4}}].

Data collection: APEX2 (Bruker, 2008[Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2008[Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: CaRine (Boudias & Monceau, 1998[Boudias, C. & Monceau, D. (1998). CaRine. CaRine Crystallography, DIVERGENT S.A., Compiègne, France.]) and ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Supporting information


Comment top

The title compound is the third polymorph of composition Lu(PO3)3 besides the monoclinic form described by Höppe & Sedlmaier (2007) and Yuan et al. (2008) and the trigonal form more recently reported by Bejaoui et al. (2008). The title compound is also the less dense polymorph with a calculated density of 3.451 Mg.m3 versus 3.587 Mg.m3 for the trigonal and 3.708 Mg.m3 for the monoclinic form and is probably the highest temperature form. This cyclotetraphosphate belongs to a structural type (cubic, with space group I43d) known since 1927 through the archetype Al4(P4O12)3 determined by Hendricks & Wyckoff (1927). Then Pauling & Sherman (1937) gave the first description of the structure and reported roughly estimated atomic coordinates deduced from geometrical considerations. Since this time only five members of this family, viz. Cr4III(P4O12)3 (Rémy & Boullé, 1964), Ti4III(P4O12)3 (Liebau & Williams, 1964), Fe4III(P4O12)3 (d'Yvoire et al., 1962), Sc4III(P4O12)3 (Bagieu-Beucher, 1976; Mezentseva et al.,1977 and Smolin et al., 1978) and Yb4III(P4O12)3 (Chudinova, 1979), have been identified. Corresponding unit cell parameters are listed in Durif (1995). Among these isotypic compounds only the structure of the Sc4(P4O12)3 cyclotetraphosphate has almost simultaneously been refined from single-crystal data by Bagieu-Beucher & Guittel (1978) and Smolin et al. (1978). Their refinements confirmed the description of Pauling & Sherman (1937) according to which all the crystallographically independent atoms except the AIII element (.3. symmetry) are in general positions. The structure is built of four-membered phosphate ring anions (P4O12)4- (Fig. 1), isolated from each other and further linked by LuO6 octahedra by sharing corners. Each LuO6 octahedron is linked to six (P4O12)4- rings (Fig. 2a) while each (P4O12)4- ring is linked to eight LuO6 octahedra (Fig. 2b) through oxygen atoms with shorter P—O distances (1.464 (4) and 1.481 (4) Å). The (P4O12)4- ring anions are located around the 12a Wyckoff positions of space group I43d and exhibit 4 symmetry. Comparison of the (P4O12)4- ring anions in both Sc4(P4O12)3 and Lu4(P4O12)3 structures shows these two ring anions being geometrically quite identical with alternating upward- and downward-pointing tetrahedra and P—O—P angles of 137.1° and 136.9 (2)°, respectively. The P—O distances in the PO4 groups are identical within their e.s.d.. The four bridging oxygen atoms of these ring anions are located at the apices of a flattened tetrahedron with characteristic angles of 148.22° and 94.30° for Sc and 147.95° and 94.37° for the Lu cyclotetraphosphate. The LuO6 octahedron is very slightly distorted along a threefold axis, resulting in two sets of Lu—O distances equal to 2.182 (3) and 2.185 (4) Å, respectively.

Related literature top

The title compound belongs to a structural type discovered a long time ago through the Al4(P4O12)3 member, the structure of which was first investigated by Hendricks & Wyckoff (1927) and then described by Pauling & Sherman (1937). Since then, five isotypic compounds have been characterized: Cr4(P4O12)3 (Rémy & Boullé, 1964); Ti4(P4O12)3 (Liebau & Williams, 1964); Fe4(P4O12)3 (d'Yvoire et al., 1962); Sc4(P4O12)3 (Bagieu-Beucher, 1976; Mezentseva et al., 1977; Bagieu-Beucher & Guitel, 1978; Smolin et al. 1978) and Yb4(P4O12)3 (Chudinova, 1979). For a review of the crystal chemistry of cyclotetraphosphates, see: Durif (1995). For other polymorphs of composition Lu(PO3)3, see: Höppe & Sedlmaier (2007); Yuan et al. (2008); Bejaoui et al. (2008).

Experimental top

Single crystals of the title compound were obtained by solid state reaction while attempting to synthesized a long chain polyphosphate by reacting Lu2O3 with (NH4)H2PO4 and Rb2CO3 in an alumina boat. A mixture of these reagents in the molar ratio 27 : 85.5 : 8.7 was used for the synthesis. The mixture was successively heated at 473 K for 24 hours, then at 573 K for 24 additional hours and finally at 813 K for 24 hours. Then the sample was cooled down to 683 K at the rate of 3 K h-1 and maintained at this temperature for 36 hours. Finally, the sample was cooled down to room temperature by shutting the muffle furnace off. Single crystals were extracted from the batch by washing with hot water and filtering. The crystals were dried at 353 K in an oven. A translucent octahedral crystal of the title compound was selected for the structure refinement.

Refinement top

The highest residual peak in the final difference Fourier map was located 0.87 Å from atom Lu and the deepest hole was located 0.99 Å from atom Lu.

Structure description top

The title compound is the third polymorph of composition Lu(PO3)3 besides the monoclinic form described by Höppe & Sedlmaier (2007) and Yuan et al. (2008) and the trigonal form more recently reported by Bejaoui et al. (2008). The title compound is also the less dense polymorph with a calculated density of 3.451 Mg.m3 versus 3.587 Mg.m3 for the trigonal and 3.708 Mg.m3 for the monoclinic form and is probably the highest temperature form. This cyclotetraphosphate belongs to a structural type (cubic, with space group I43d) known since 1927 through the archetype Al4(P4O12)3 determined by Hendricks & Wyckoff (1927). Then Pauling & Sherman (1937) gave the first description of the structure and reported roughly estimated atomic coordinates deduced from geometrical considerations. Since this time only five members of this family, viz. Cr4III(P4O12)3 (Rémy & Boullé, 1964), Ti4III(P4O12)3 (Liebau & Williams, 1964), Fe4III(P4O12)3 (d'Yvoire et al., 1962), Sc4III(P4O12)3 (Bagieu-Beucher, 1976; Mezentseva et al.,1977 and Smolin et al., 1978) and Yb4III(P4O12)3 (Chudinova, 1979), have been identified. Corresponding unit cell parameters are listed in Durif (1995). Among these isotypic compounds only the structure of the Sc4(P4O12)3 cyclotetraphosphate has almost simultaneously been refined from single-crystal data by Bagieu-Beucher & Guittel (1978) and Smolin et al. (1978). Their refinements confirmed the description of Pauling & Sherman (1937) according to which all the crystallographically independent atoms except the AIII element (.3. symmetry) are in general positions. The structure is built of four-membered phosphate ring anions (P4O12)4- (Fig. 1), isolated from each other and further linked by LuO6 octahedra by sharing corners. Each LuO6 octahedron is linked to six (P4O12)4- rings (Fig. 2a) while each (P4O12)4- ring is linked to eight LuO6 octahedra (Fig. 2b) through oxygen atoms with shorter P—O distances (1.464 (4) and 1.481 (4) Å). The (P4O12)4- ring anions are located around the 12a Wyckoff positions of space group I43d and exhibit 4 symmetry. Comparison of the (P4O12)4- ring anions in both Sc4(P4O12)3 and Lu4(P4O12)3 structures shows these two ring anions being geometrically quite identical with alternating upward- and downward-pointing tetrahedra and P—O—P angles of 137.1° and 136.9 (2)°, respectively. The P—O distances in the PO4 groups are identical within their e.s.d.. The four bridging oxygen atoms of these ring anions are located at the apices of a flattened tetrahedron with characteristic angles of 148.22° and 94.30° for Sc and 147.95° and 94.37° for the Lu cyclotetraphosphate. The LuO6 octahedron is very slightly distorted along a threefold axis, resulting in two sets of Lu—O distances equal to 2.182 (3) and 2.185 (4) Å, respectively.

The title compound belongs to a structural type discovered a long time ago through the Al4(P4O12)3 member, the structure of which was first investigated by Hendricks & Wyckoff (1927) and then described by Pauling & Sherman (1937). Since then, five isotypic compounds have been characterized: Cr4(P4O12)3 (Rémy & Boullé, 1964); Ti4(P4O12)3 (Liebau & Williams, 1964); Fe4(P4O12)3 (d'Yvoire et al., 1962); Sc4(P4O12)3 (Bagieu-Beucher, 1976; Mezentseva et al., 1977; Bagieu-Beucher & Guitel, 1978; Smolin et al. 1978) and Yb4(P4O12)3 (Chudinova, 1979). For a review of the crystal chemistry of cyclotetraphosphates, see: Durif (1995). For other polymorphs of composition Lu(PO3)3, see: Höppe & Sedlmaier (2007); Yuan et al. (2008); Bejaoui et al. (2008).

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: CaRine (Boudias & Monceau, 1998) and ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. ORTEP-3 view of the four-membered phosphate (P4O12)4- ring anion. Displacement ellipsoids are drawn at the 50% probability level. Symmetry codes: (i) 1-z, 3/2-x, y ; (ii) 3/4+y, 5/4-x, 3/4-z ; (iii) 5/4-y, -3/4+x,3/4-z ; (iv) -1/4+x, 1/4-z, 3/4-y ; (v) 9/4-x, 1/4+z, 3/4-y ;(vi) 2-x, 1/2-y, z ; (vii) 1+z, -1+x, y.
[Figure 2] Fig. 2. Partial view of the Lu4(P4O12)3 structure showing: (a) the connections between the LuO6 octahedron and the (P4O12)4- ring anions, (b) the connections between the (P4O12)4- ring anion and the LuO6 octahedra.
Tetralutetium(III) tris(cyclotetraphosphate) top
Crystal data top
Lu4(P4O12)3Dx = 3.451 Mg m3
Mr = 1647.52Mo Kα radiation, λ = 0.71073 Å
Cubic, I43dCell parameters from 1548 reflections
Hall symbol: I -4bd 2c 3θ = 3.4–30.3°
a = 14.6920 (6) ŵ = 13.08 mm1
V = 3171.3 (2) Å3T = 296 K
Z = 4Truncated octahedron, colourless
F(000) = 30080.18 × 0.10 × 0.08 mm
Data collection top
Bruker APEXII CCD
diffractometer
717 independent reflections
Radiation source: fine-focus sealed tube659 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.034
Detector resolution: 8.3333 pixels mm-1θmax = 30.4°, θmin = 3.9°
φ and ω scansh = 1611
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
k = 620
Tmin = 0.534, Tmax = 0.746l = 199
3088 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.020 w = 1/[σ2(Fo2) + (0.0088P)2]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.038(Δ/σ)max < 0.001
S = 1.03Δρmax = 0.90 e Å3
717 reflectionsΔρmin = 0.67 e Å3
41 parametersAbsolute structure: Flack (1983), 272 Friedel pairs
0 restraintsAbsolute structure parameter: 0.000 (15)
0 constraints
Crystal data top
Lu4(P4O12)3Z = 4
Mr = 1647.52Mo Kα radiation
Cubic, I43dµ = 13.08 mm1
a = 14.6920 (6) ÅT = 296 K
V = 3171.3 (2) Å30.18 × 0.10 × 0.08 mm
Data collection top
Bruker APEXII CCD
diffractometer
717 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
659 reflections with I > 2σ(I)
Tmin = 0.534, Tmax = 0.746Rint = 0.034
3088 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0200 restraints
wR(F2) = 0.038Δρmax = 0.90 e Å3
S = 1.03Δρmin = 0.67 e Å3
717 reflectionsAbsolute structure: Flack (1983), 272 Friedel pairs
41 parametersAbsolute structure parameter: 0.000 (15)
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.

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
xyzUiso*/Ueq
Lu0.896610 (13)0.396610 (13)0.103390 (13)0.00602 (8)
P0.95737 (9)0.37294 (9)0.33447 (9)0.0077 (2)
O11.0613 (2)0.3432 (2)0.3430 (2)0.0128 (7)
O21.0325 (2)0.3642 (3)0.0522 (2)0.0188 (8)
O30.9295 (2)0.3498 (3)0.2404 (2)0.0142 (7)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Lu0.00602 (8)0.00602 (8)0.00602 (8)0.00039 (8)0.00039 (8)0.00039 (8)
P0.0097 (5)0.0051 (6)0.0082 (6)0.0017 (5)0.0008 (5)0.0015 (4)
O10.0113 (15)0.0146 (18)0.0123 (17)0.0007 (15)0.0025 (14)0.0054 (17)
O20.0103 (17)0.024 (2)0.022 (2)0.0016 (18)0.0015 (16)0.0014 (18)
O30.0202 (19)0.0141 (19)0.0084 (16)0.0012 (16)0.0050 (15)0.0023 (16)
Geometric parameters (Å, º) top
Lu—O3i2.182 (3)P—O2iii1.464 (4)
Lu—O3ii2.182 (3)P—O31.481 (4)
Lu—O32.182 (3)P—O1iv1.583 (3)
Lu—O2i2.185 (4)P—O11.594 (3)
Lu—O2ii2.185 (4)O1—Pv1.583 (3)
Lu—O22.185 (4)O2—Pvi1.464 (4)
O3i—Lu—O3ii89.06 (14)O3—Lu—O292.64 (13)
O3i—Lu—O389.06 (14)O2i—Lu—O287.72 (15)
O3ii—Lu—O389.06 (14)O2ii—Lu—O287.72 (15)
O3i—Lu—O2i92.64 (13)O2iii—P—O3118.0 (2)
O3ii—Lu—O2i178.26 (14)O2iii—P—O1iv107.3 (2)
O3—Lu—O2i90.59 (14)O3—P—O1iv111.5 (2)
O3i—Lu—O2ii90.59 (14)O2iii—P—O1109.2 (2)
O3ii—Lu—O2ii92.64 (13)O3—P—O1106.0 (2)
O3—Lu—O2ii178.26 (14)O1iv—P—O1103.9 (2)
O2i—Lu—O2ii87.72 (15)Pv—O1—P136.9 (2)
O3i—Lu—O2178.26 (14)Pvi—O2—Lu164.9 (2)
O3ii—Lu—O290.59 (14)P—O3—Lu148.2 (2)
Symmetry codes: (i) z+1, x1/2, y+1/2; (ii) y+1/2, z+1/2, x+1; (iii) z+1, x+3/2, y; (iv) y+5/4, x3/4, z+3/4; (v) y+3/4, x+5/4, z+3/4; (vi) y+3/2, z, x+1.

Experimental details

Crystal data
Chemical formulaLu4(P4O12)3
Mr1647.52
Crystal system, space groupCubic, I43d
Temperature (K)296
a (Å)14.6920 (6)
V3)3171.3 (2)
Z4
Radiation typeMo Kα
µ (mm1)13.08
Crystal size (mm)0.18 × 0.10 × 0.08
Data collection
DiffractometerBruker APEXII CCD
Absorption correctionMulti-scan
(SADABS; Bruker, 2008)
Tmin, Tmax0.534, 0.746
No. of measured, independent and
observed [I > 2σ(I)] reflections
3088, 717, 659
Rint0.034
(sin θ/λ)max1)0.712
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.020, 0.038, 1.03
No. of reflections717
No. of parameters41
Δρmax, Δρmin (e Å3)0.90, 0.67
Absolute structureFlack (1983), 272 Friedel pairs
Absolute structure parameter0.000 (15)

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), CaRine (Boudias & Monceau, 1998) and ORTEP-3 (Farrugia, 1997), SHELXTL (Sheldrick, 2008).

Selected bond lengths (Å) top
Lu—O3i2.182 (3)Lu—O22.185 (4)
Lu—O3ii2.182 (3)P—O2iii1.464 (4)
Lu—O32.182 (3)P—O31.481 (4)
Lu—O2i2.185 (4)P—O1iv1.583 (3)
Lu—O2ii2.185 (4)P—O11.594 (3)
Symmetry codes: (i) z+1, x1/2, y+1/2; (ii) y+1/2, z+1/2, x+1; (iii) z+1, x+3/2, y; (iv) y+5/4, x3/4, z+3/4.
 

References

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