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

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Ammonium ytterbium(III) diphosphate(V)

aInstitute of Physics, Na Slovance 2, 182 21 Praha 8, Czech Republic, and bDepartment of Chemistry, Faculty of Sciences, University Mohammed 1st, PO Box 717, 60 000 Oujda, Morocco
*Correspondence e-mail: fejfarov@fzu.cz

(Received 21 November 2008; accepted 25 November 2008; online 29 November 2008)

The title compound, NH4YbP2O7, crystallizes in the KAlP2O7 structure type and consists of distorted YbO6 octa­hedra and bent P2O74− diphosphate units forming together a three-dimensional network. There are channels in the structure running along the c axis, where the NH4+ cations are located. They are connected via N—H⋯O hydrogen bonds to the terminal O atoms of the diphosphate anions.

Related literature

Isotypic compounds were reported by Man-Rong et al. (2005[Man-Rong, L., Wei, L., Hao-Hong, C., Xin-Xin, Y., Zan-Bin, W., Dun-Hua, C., Mu, G. & Jing-Tai, Z. (2005). Eur. J. Inorg. Chem. pp. 4693-4696.]), [NH4LuP2O7]; Horchani-Naifer & Férid (2007[Horchani-Naifer, K. & Férid, M. (2007). Acta Cryst. E63, i33-i34.]), [YbP2O7]; Jansen et al. (1991[Jansen, M., Wu, G. Q. & Koenigstein, K. (1991). Z. Kristallogr. 197, 245-246.]), [CsYbP2O7], that all crystallize with the KAlP2O7 structure type (Ng & Calvo, 1973[Ng, H. N. & Calvo, C. (1973). Can. J. Chem. 51, 2613-2620.]). For the crystal structures of other isoformular rare earth diphosphates, see: Hamady & Jouini (1996[Hamady, A. & Jouini, T. (1996). Acta Cryst. C52, 2949-2951.]), [NaYP2O7]; Férid et al. (2004[Férid, M., Horchani, K. & Amami, J. (2004). Mater. Res. Bull. 39, 1949-1955.]), [NaEuP2O7]; Ferid et al. (2004[Férid, M., Horchani, K. & Amami, J. (2004). Mater. Res. Bull. 39, 1949-1955.][Ferid, M., Horchani-Naifer, K. & Trabelsi-Ayedi, M. (2004). Z. Kristallogr. New Cryst. Struct. 219, 353-354.]), [NaYbP2O7]; Férid & Horchani-Naifer (2004[Férid, M. & Horchani-Naifer, K. (2004). Mater. Res. Bull. 39, 2209-2217.]), [NaLaP2O7]; Horchani-Naifer & Férid (2005[Horchani-Naifer, K. & Férid, M. (2005). Solid State Ionics, 176, 1949-1953.]), [NaCeP2O7]; Hamady et al. (1994[Hamady, A., Faouzi Zid, M. & Jouini, T. (1994). J. Solid State Chem. 113, 120-124.]) and Yuan et al. (2007[Yuan, J., Zhang, H., Chen, H., Yang, X., Zhao, J. & Gu, M. (2007). J. Solid State Chem. 180, 3381-3387.]), [KYP2O7]. Possible applications of rare earth phosphates were discussed by Yamada et al. (1974[Yamada, T., Otsuka, K. & Nakano, J. (1974). J. Appl. Phys. 45, 5096-5097.]); Hong (1975[Hong, H. Y. P. (1975). Mater. Res. Bull. 10, 1105-1110.]); Bimberg et al. (1975[Bimberg, D., Robbins, D. J., Wight, D. R. & Jeser, J. P. (1975). Appl. Phys. Lett. 27, 67-68.]). For background on crystallographic software, see: Becker & Coppens (1974[Becker, P. J. & Coppens, P. (1974). Acta Cryst. A30, 129-147.]).

Experimental

Crystal data
  • NH4YbP2O7

  • Mr = 365

  • Monoclinic, P 21 /c

  • a = 7.6468 (2) Å

  • b = 10.9119 (2) Å

  • c = 8.6129 (3) Å

  • β = 105.645 (3)°

  • V = 692.04 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 13.97 mm−1

  • T = 120 K

  • 0.26 × 0.08 × 0.07 mm

Data collection
  • Oxford Diffraction XCalibur 2 diffractometer with Sapphire 2 area detector

  • Absorption correction: analytical [implemented in CrysAlis RED (Oxford Diffraction, 2008[Oxford Diffraction (2008). CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]), according to Clark & Reid (1995[Clark, R. C. & Reid, J. S. (1995). Acta Cryst. A51, 887-897.])] Tmin = 0.169, Tmax = 0.545

  • 8574 measured reflections

  • 1437 independent reflections

  • 1362 reflections with I > 3σ(I)

  • Rint = 0.023

Refinement
  • R[F2 > 2σ(F2)] = 0.016

  • wR(F2) = 0.061

  • S = 1.32

  • 1437 reflections

  • 113 parameters

  • 4 restraints

  • Only H-atom coordinates refined

  • Δρmax = 0.58 e Å−3

  • Δρmin = −0.50 e Å−3

Table 1
Selected geometric parameters (Å, °)

Yb1—O1 2.240 (3)
Yb1—O2i 2.158 (4)
Yb1—O4ii 2.230 (3)
Yb1—O5 2.224 (3)
Yb1—O6iii 2.191 (4)
Yb1—O7iv 2.195 (3)
P1—O1 1.529 (3)
P1—O2 1.498 (5)
P1—O3 1.611 (4)
P1—O4 1.525 (3)
P2—O3 1.622 (4)
P2—O5 1.532 (3)
P2—O6 1.507 (4)
P2—O7 1.514 (3)
P1—O3—P2 127.40 (19)
Symmetry codes: (i) [x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]; (ii) [-x+1, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]; (iii) [x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]; (iv) [-x+2, y-{\script{1\over 2}}, -z+{\script{3\over 2}}].

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O7v 0.87 (4) 2.52 (5) 3.381 (5) 168 (4)
N1—H2⋯O4vi 0.88 (4) 2.03 (5) 2.888 (5) 166 (4)
N1—H3⋯O5vii 0.87 (4) 2.00 (4) 2.873 (6) 177 (7)
N1—H4⋯O1 0.86 (5) 2.26 (4) 2.916 (5) 132 (4)
Symmetry codes: (v) x-1, y, z; (vi) -x+1, -y+1, -z+1; (vii) [x-1, -y+{\script{1\over 2}}, z-{\script{1\over 2}}].

Data collection: CrysAlis CCD (Oxford Diffraction, 2005[Oxford Diffraction (2005). CrysAlis CCD. Oxford Diffraction Ltd, Abingdon, England.]); cell refinement: CrysAlis RED (Oxford Diffraction, 2008[Oxford Diffraction (2008). CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]); data reduction: CrysAlis RED; program(s) used to solve structure: SIR2002 (Burla et al., 2003[Burla, M. C., Camalli, M., Carrozzini, B., Cascarano, G. L., Giacovazzo, C., Polidori, G. & Spagna, R. (2003). J. Appl. Cryst. 36, 1103.]); program(s) used to refine structure: JANA2006 (Petříček et al., 2007[Petříček, V., Dušek, M. & Palatinus, L. (2007). JANA2006. Institute of Physics, Praha, Czech Republic.]); molecular graphics: DIAMOND (Brandenburg & Putz, 2005[Brandenburg, K. & Putz, H. (2005). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: JANA2006.

Supporting information


Comment top

Rare earth phosphates have many potential applications in the field of optical materials including laser phosphors (Yamada et al., 1974; Hong, 1975; Bimberg et al., 1975). Their crystal structures depend on the ionic radii of the alkali metal and the rare earth ions. The two AYbP2O7 (A = Cs (Jansen et al., 1991), K (Horchani-Naifer & Férid, 2007)) structures known so far belong to the KAlP2O7 structure type (Ng & Calvo, 1973) and crystallize in space group P21/c. For the correspondent isoformular sodium rare earth diphosphates, several other structures have been described, for instance NaYP2O7 in space group P21 (Hamady & Jouini, 1996), NaLnP2O7 (Ln = Eu (Férid, Horchani & Amami, 2004), Yb (Ferid et al., 2004)) in space group P21/n, and NaLnP2O7 (Ln = La (Férid & Horchani-Naifer, 2004), Ce (Horchani-Naifer & Férid, 2005) in space group Pnma. KYP2O7 is dimorphic and can adopt the KAlP2O7 structure type (Yuan et al., 2007), or a structure in space group Cmcm (Hamady et al., 1994).

In the present paper we report the crystal structure of NH4YbP2O7. This compound is isotypic with NH4LuP2O7 (Man-Rong et al. 2005), KYbP2O7 (Horchani-Naifer & Férid, 2007) and CsYbP2O7 (Jansen et al., 1991). The Yb atom is coordinated by six oxygen atoms forming a distorted octahedron that belong to five symmetry-related P2O74- anions (Fig. 1). The average Yb—O bond lenght is 2.206 Å (Table 1). The diphosphate anion is bent with a bridging angle of 127.40 (19) °. The three-dimensional network of YbO6 and P2O74- units forms channels running along the c direcion in which the NH4+ cations are located (Fig. 2). Each NH4+ cation is connected via N—H···O hydrogen bonds to four different P2O74- anions (Table 2).

Related literature top

Isotypic compounds were reported by Man-Rong et al. (2005), [NH4LuP2O7]; Horchani-Naifer & Férid (2007), [YbP2O7]; Jansen et al. (1991), [CsYbP2O7], that all crystallize with the KAlP2O7 structure type (Ng & Calvo, 1973). For the crystal structures of other isoformular rare earth diphosphates, see: Hamady & Jouini (1996), [NaYP2O7]; Férid, Horchani & Amami (2004), [NaEuP2O7]; Férid et al. (2004), [NaYbP2O7]; Férid & Horchani-Naifer (2004), [NaLaP2O7]; Horchani-Naifer & Férid (2005), [NaCeP2O7]; Hamady et al. (1994) and Yuan et al. (2007), [KYP2O7]. Possible applications of rare earth phosphates were discussed by Yamada et al. (1974); Hong (1975); Bimberg et al. (1975). For background on crystallographic software, see: Becker & Coppens (1974). For related literature, see: Ferid et al. (2004).

Experimental top

Three solutions have been mixed in a beaker to prepare the title compound: NH4OH (20 ml, 0.1 mmol), YbCl3.6H2O (20 ml, 0.1 mmol) and Na4P2O7 (20 ml, 0.1 mmol). The pH of the mixture was controlled with diluted hydrochloric acid to be slightly acidic, and the solution was stirred for two hours at room temperature. Crystals suitable for X-ray analysis were formed after a few days.

Refinement top

All hydrogen atoms were discernible in difference Fourier maps and could be refined to reasonable geometry. The N—H distances were restrained to 0.87 Å with σ of 0.02. The isotropic atomic displacement parameters of all hydrogen atoms were refined with 1.2×Ueq of the N atom.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2005); cell refinement: CrysAlis RED (Oxford Diffraction, 2008); data reduction: CrysAlis RED (Oxford Diffraction, 2008); program(s) used to solve structure: SIR2002 (Burla et al., 2003); program(s) used to refine structure: JANA2006 (Petříček et al., 2007); molecular graphics: DIAMOND (Brandenburg & Putz, 2005); software used to prepare material for publication: JANA2006 (Petříček et al., 2007).

Figures top
[Figure 1] Fig. 1. Part of the structure of NH4YbP2O7. Displacement ellipsoids are drawn at the 50% probability level. [Symmetry codes: (i) 1 - x,-1/2 + y, 1.5 - z; (ii) x, 0.5 - y, -1/2 + z; (iii) x, 0.5 - y, 1/2 + z; (iv) 2 - x, -1/2 + y, 1.5 - z; (v) 1 - x, 1 - y, 1 - z; (vi} -1 + x, 0.5 - y, -1/2 + z; (vii) -1 + x, y, z.]
[Figure 2] Fig. 2. The packing of NH4YbP2O7 viewed along c. Colors: Pink (P2O7), grey (YbO6), blue balls (N), black balls (H).
Ammonium ytterbium(III) diphosphate(V) top
Crystal data top
NH4YbP2O7F(000) = 668
Mr = 365Dx = 3.502 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 8929 reflections
a = 7.6468 (2) Åθ = 2.8–26.5°
b = 10.9119 (2) ŵ = 13.97 mm1
c = 8.6129 (3) ÅT = 120 K
β = 105.645 (3)°Prism, colorless
V = 692.04 (3) Å30.26 × 0.08 × 0.07 mm
Z = 4
Data collection top
Oxford Diffraction XCalibur 2 with Sapphire 2 area detector
diffractometer
1437 independent reflections
Radiation source: X-ray tube1362 reflections with I > 3σ(I)
Graphite monochromatorRint = 0.023
Detector resolution: 8.3438 pixels mm-1θmax = 26.5°, θmin = 2.8°
Rotation method data acquisition using ω scansh = 99
Absorption correction: analytical
[implemented in CrysAlis RED (Oxford Diffraction, 2008), according to Clark & Reid (1995)]
k = 1313
Tmin = 0.169, Tmax = 0.545l = 1010
8574 measured reflections
Refinement top
Refinement on F2Only H-atom coordinates refined
R[F2 > 2σ(F2)] = 0.016Weighting scheme based on measured s.u.'s w = 1/[σ2(I) + 0.0016I2]
wR(F2) = 0.061(Δ/σ)max = 0.039
S = 1.32Δρmax = 0.58 e Å3
1437 reflectionsΔρmin = 0.50 e Å3
113 parametersExtinction correction: B-C type 1 Lorentzian isotropic (Becker & Coppens, 1974)
4 restraintsExtinction coefficient: 170 (60)
4 constraints
Crystal data top
NH4YbP2O7V = 692.04 (3) Å3
Mr = 365Z = 4
Monoclinic, P21/cMo Kα radiation
a = 7.6468 (2) ŵ = 13.97 mm1
b = 10.9119 (2) ÅT = 120 K
c = 8.6129 (3) Å0.26 × 0.08 × 0.07 mm
β = 105.645 (3)°
Data collection top
Oxford Diffraction XCalibur 2 with Sapphire 2 area detector
diffractometer
1437 independent reflections
Absorption correction: analytical
[implemented in CrysAlis RED (Oxford Diffraction, 2008), according to Clark & Reid (1995)]
1362 reflections with I > 3σ(I)
Tmin = 0.169, Tmax = 0.545Rint = 0.023
8574 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0164 restraints
wR(F2) = 0.061Only H-atom coordinates refined
S = 1.32Δρmax = 0.58 e Å3
1437 reflectionsΔρmin = 0.50 e Å3
113 parameters
Special details top

Refinement. The refinement was carried out against all reflections. The conventional R-factor is always based on F. The goodness of fit as well as the weighted R-factor are based on F and F2 for refinement carried out on F and F2, respectively. The threshold expression is used only for calculating R-factors etc. and it is not relevant to the choice of reflections for refinement.

The program used for refinement, Jana2006, uses the weighting scheme based on the experimental expectations, see _refine_ls_weighting_details, that does not force S to be one. Therefore the values of S are usually larger than the ones from the SHELX program.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Yb10.73470 (3)0.100256 (15)0.753623 (18)0.00555 (9)
P10.63175 (18)0.40147 (9)0.81812 (14)0.0080 (4)
P20.93914 (15)0.36312 (10)0.68708 (13)0.0070 (3)
O10.5777 (4)0.2746 (3)0.7457 (4)0.0124 (10)
O20.6416 (6)0.4080 (3)0.9940 (5)0.0254 (14)
O30.8335 (4)0.4300 (3)0.8037 (4)0.0126 (9)
O40.5107 (4)0.5010 (3)0.7202 (3)0.0097 (9)
O50.9555 (4)0.2277 (3)0.7359 (4)0.0121 (10)
O60.8260 (6)0.3855 (3)0.5169 (5)0.0183 (12)
O71.1241 (4)0.4235 (3)0.7273 (4)0.0142 (10)
N10.3131 (6)0.3233 (4)0.4381 (5)0.0183 (13)
H10.281 (7)0.348 (5)0.523 (4)0.0219*
H20.365 (7)0.385 (3)0.403 (6)0.0219*
H30.206 (4)0.306 (5)0.375 (5)0.0219*
H40.373 (7)0.267 (4)0.501 (5)0.0219*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Yb10.00611 (15)0.00443 (15)0.00616 (16)0.00018 (5)0.00173 (9)0.00025 (5)
P10.0101 (6)0.0088 (6)0.0056 (5)0.0056 (4)0.0027 (5)0.0006 (4)
P20.0066 (5)0.0058 (5)0.0084 (5)0.0016 (4)0.0017 (4)0.0016 (4)
O10.0142 (16)0.0076 (15)0.0178 (16)0.0019 (12)0.0085 (13)0.0023 (12)
O20.034 (3)0.039 (2)0.0043 (17)0.0210 (17)0.0062 (17)0.0013 (14)
O30.0073 (15)0.0117 (14)0.0158 (16)0.0000 (12)0.0019 (13)0.0036 (13)
O40.0093 (14)0.0097 (13)0.0102 (14)0.0026 (12)0.0028 (11)0.0041 (12)
O50.0088 (15)0.0113 (15)0.0166 (16)0.0007 (12)0.0041 (12)0.0045 (12)
O60.017 (2)0.0277 (19)0.0086 (18)0.0005 (14)0.0015 (15)0.0090 (14)
O70.0093 (16)0.0101 (13)0.0228 (17)0.0036 (13)0.0035 (14)0.0014 (12)
N10.017 (2)0.021 (2)0.013 (2)0.0069 (17)0.0014 (17)0.0046 (16)
Geometric parameters (Å, º) top
Yb1—O12.240 (3)P1—O41.525 (3)
Yb1—O2i2.158 (4)P2—O31.622 (4)
Yb1—O4ii2.230 (3)P2—O51.532 (3)
Yb1—O52.224 (3)P2—O61.507 (4)
Yb1—O6iii2.191 (4)P2—O71.514 (3)
Yb1—O7iv2.195 (3)N1—H10.87 (5)
P1—O11.529 (3)N1—H20.87 (5)
P1—O21.498 (5)N1—H30.87 (3)
P1—O31.611 (4)N1—H40.86 (4)
O1—Yb1—O2i88.83 (13)O2—P1—O3106.3 (2)
O1—Yb1—O4ii87.53 (11)O2—P1—O4112.5 (2)
O1—Yb1—O582.94 (12)O3—P1—O4105.70 (17)
O1—Yb1—O6iii89.43 (12)O3—P2—O5106.33 (19)
O1—Yb1—O7iv175.63 (13)O3—P2—O6106.2 (2)
O2i—Yb1—O4ii91.87 (14)O3—P2—O7104.64 (18)
O2i—Yb1—O589.99 (15)O5—P2—O6113.98 (18)
O2i—Yb1—O6iii178.23 (14)O5—P2—O7110.79 (17)
O2i—Yb1—O7iv93.37 (13)O6—P2—O7114.1 (2)
O4ii—Yb1—O5170.25 (11)P1—O3—P2127.40 (19)
O4ii—Yb1—O6iii88.39 (13)P1—O4—H2v115.2 (13)
O4ii—Yb1—O7iv88.63 (12)P2—O5—H3vi109.5 (14)
O5—Yb1—O6iii89.47 (13)H1—N1—H2108 (5)
O5—Yb1—O7iv100.82 (12)H1—N1—H399 (4)
O6iii—Yb1—O7iv88.39 (12)H1—N1—H485 (5)
O1—P1—O2113.0 (2)H2—N1—H3113 (4)
O1—P1—O3107.61 (19)H2—N1—H4123 (5)
O1—P1—O4111.26 (16)H3—N1—H4119 (4)
Symmetry codes: (i) x, y+1/2, z1/2; (ii) x+1, y1/2, z+3/2; (iii) x, y+1/2, z+1/2; (iv) x+2, y1/2, z+3/2; (v) x+1, y+1, z+1; (vi) x+1, y+1/2, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O7vii0.87 (4)2.52 (5)3.381 (5)168 (4)
N1—H2···O4v0.88 (4)2.03 (5)2.888 (5)166 (4)
N1—H3···O5viii0.87 (4)2.00 (4)2.873 (6)177 (7)
N1—H4···O10.86 (5)2.26 (4)2.916 (5)132 (4)
Symmetry codes: (v) x+1, y+1, z+1; (vii) x1, y, z; (viii) x1, y+1/2, z1/2.

Experimental details

Crystal data
Chemical formulaNH4YbP2O7
Mr365
Crystal system, space groupMonoclinic, P21/c
Temperature (K)120
a, b, c (Å)7.6468 (2), 10.9119 (2), 8.6129 (3)
β (°) 105.645 (3)
V3)692.04 (3)
Z4
Radiation typeMo Kα
µ (mm1)13.97
Crystal size (mm)0.26 × 0.08 × 0.07
Data collection
DiffractometerOxford Diffraction XCalibur 2 with Sapphire 2 area detector
diffractometer
Absorption correctionAnalytical
[implemented in CrysAlis RED (Oxford Diffraction, 2008), according to Clark & Reid (1995)]
Tmin, Tmax0.169, 0.545
No. of measured, independent and
observed [I > 3σ(I)] reflections
8574, 1437, 1362
Rint0.023
(sin θ/λ)max1)0.628
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.016, 0.061, 1.32
No. of reflections1437
No. of parameters113
No. of restraints4
H-atom treatmentOnly H-atom coordinates refined
Δρmax, Δρmin (e Å3)0.58, 0.50

Computer programs: CrysAlis CCD (Oxford Diffraction, 2005), CrysAlis RED (Oxford Diffraction, 2008), SIR2002 (Burla et al., 2003), JANA2006 (Petříček et al., 2007), DIAMOND (Brandenburg & Putz, 2005).

Selected geometric parameters (Å, º) top
Yb1—O12.240 (3)P1—O21.498 (5)
Yb1—O2i2.158 (4)P1—O31.611 (4)
Yb1—O4ii2.230 (3)P1—O41.525 (3)
Yb1—O52.224 (3)P2—O31.622 (4)
Yb1—O6iii2.191 (4)P2—O51.532 (3)
Yb1—O7iv2.195 (3)P2—O61.507 (4)
P1—O11.529 (3)P2—O71.514 (3)
P1—O3—P2127.40 (19)
Symmetry codes: (i) x, y+1/2, z1/2; (ii) x+1, y1/2, z+3/2; (iii) x, y+1/2, z+1/2; (iv) x+2, y1/2, z+3/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O7v0.87 (4)2.52 (5)3.381 (5)168 (4)
N1—H2···O4vi0.88 (4)2.03 (5)2.888 (5)166 (4)
N1—H3···O5vii0.87 (4)2.00 (4)2.873 (6)177 (7)
N1—H4···O10.86 (5)2.26 (4)2.916 (5)132 (4)
Symmetry codes: (v) x1, y, z; (vi) x+1, y+1, z+1; (vii) x1, y+1/2, z1/2.
 

Acknowledgements

We acknowledge the Grant Agency of the Czech Republic for grant No. 202/06/0757.

References

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