Ba4GaN3O

Hashimoto, T.; Yamane, H.

doi:10.1107/S1600536814010472

inorganic compounds

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ISSN: 2056-9890

Volume 70| Part 6| June 2014| Page i28

doi:10.1107/S1600536814010472

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Ba₄GaN₃O

Takayuki Hashimoto ^a and Hisanori Yamane ^a ^*

^aInstitute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
^*Correspondence e-mail: yamane@tagen.tohoku.ac.jp

Edited by E. F. C. Herdtweck, Technischen Universität München, Germany (Received 24 April 2014; accepted 8 May 2014; online 17 May 2014)

Red transparant platelet-shaped single crystals of tetrabarium gallium trinitride oxide, Ba₄GaN₃O, were synthesized by the Na flux method. The crystal structure is isotypic with Sr₄GaN₃O, containing isolated triangular [GaN₃]⁶⁻ anionic groups. O²⁻ atoms are inserted between the slabs of [Ba₄GaN₃]²⁺, in which the [GaN₃]⁶⁻ groups are surrounded by Ba²⁺ atoms.

CCDC reference: 1001671

Related literature

For isotypic Sr₄GaN₃O, see: Mallinson et al. (2006 ). For the major phase in the product, Ba₃Ga₂N₄, see: Yamane & DiSalvo (1996 ). For compounds containing isolated triangular-planar [GaN₃]⁶⁻ nitridogallate anions, see: Park et al. (2003 ); Mallinson et al. (2006); Hintze & Schnick (2010 ). For details of Madelung site potential and energy calculations, see: O'Keeffe (1992 ); Orhan et al.. (2002 ); Paszkowicz et al. (2004 ); Taylor (1984 ). For details of the synthetic procedure, see: Kowach et al. (1998 ).

Experimental

Crystal data

Ba₄GaN₃O
M_r = 677.11
Orthorhombic, P b c a
a = 7.8130 (3) Å
b = 25.6453 (10) Å
c = 7.9162 (4) Å
V = 1586.14 (12) Å³
Z = 8
Mo Kα radiation
μ = 22.84 mm⁻¹
T = 293 K
0.18 × 0.13 × 0.07 mm

Data collection

Rigaku R-AXIS RAPID II diffractometer
Absorption correction: numerical (NUMABS; Higashi, 1999 ) T_min = 0.071, T_max = 0.411
14273 measured reflections
1820 independent reflections
1588 reflections with I > 2σ(I)
R_int = 0.133

Refinement

R[F² > 2σ(F²)] = 0.043
wR(F²) = 0.099
S = 1.05
1820 reflections
82 parameters
Δρ_max = 2.54 e Å⁻³
Δρ_min = −1.72 e Å⁻³

Table 1
Selected geometric parameters (Å, °)

Ba1—N1ⁱ	2.675 (8)
Ba1—N1	2.799 (9)
Ba1—N2ⁱⁱ	2.998 (7)
Ba1—O1ⁱⁱⁱ	2.999 (8)
Ba1—O1^iv	3.054 (9)
Ba2—O1^v	2.683 (9)
Ba2—N2^v	2.687 (8)
Ba2—N1ⁱⁱⁱ	2.991 (9)
Ba2—N2	3.158 (8)
Ba2—O1	3.184 (9)
Ba2—O1^vi	3.264 (10)
Ba3—N3^vii	2.730 (7)
Ba3—N3ⁱ	2.762 (8)
Ba3—N3	2.764 (7)
Ba3—N1ⁱ	2.914 (9)
Ba3—N3ⁱⁱ	2.994 (8)
Ba4—N3ⁱⁱ	2.661 (8)
Ba4—N2	2.808 (7)
Ba4—N2^v	2.862 (8)
Ba4—O1	3.133 (10)
Ba4—N1^viii	3.231 (9)
Ga1—N3	1.876 (8)
Ga1—N2	1.908 (8)
Ga1—N1ⁱⁱⁱ	1.924 (8)

N3—Ga1—N2	125.3 (3)
N3—Ga1—N1ⁱⁱⁱ	119.8 (3)
N2—Ga1—N1ⁱⁱⁱ	114.6 (4)
Symmetry codes: (i) $[x+{\script{1\over 2}}, y, -z+{\script{1\over 2}}]$ ; (ii) $[x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ ; (iii) $[x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ ; (iv) $[-x+{\script{1\over 2}}, y+{\script{1\over 2}}, z]$ ; (v) $[x-{\script{1\over 2}}, y, -z+{\script{1\over 2}}]$ ; (vi) $[-x+{\script{1\over 2}}, -y, z-{\script{1\over 2}}]$ ; (vii) $[x+{\script{1\over 2}}, -y+{\script{1\over 2}}, -z]$ ; (viii) $[x+{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+1]$ .

Data collection: RAPID-AUTO (Rigaku Corporation, 2005 ); cell refinement: RAPID-AUTO; data reduction: RAPID-AUTO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: VESTA (Momma & Izumi, 2008 ); software used to prepare material for publication: SHELXL97.

Supporting information

CCDC reference: 1001671

Crystal structure: contains datablock I. DOI: 10.1107/S1600536814010472/hp2067sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536814010472/hp2067Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536814010472/hp2067Isup3.cml

checkCIF report

Comment top

Ba₄GaN₃O is isostructural with Sr₄GaN₃O (Mallinson et al., 2006) which crystallizes in an orthorhombic cell with the space group Pbca (No. 61). The coordination environment around Ga1 site and Ba1–Ba3 sites are shown in Fig.1. Ga1 atom is bonded to N1, N2 and N3 atoms and form a triangular anionic group of [GaN₃]^6-. Ga—N bond lengths of 1.876 (8)–1.924 (8)Å are comparable with those observed in [GaN₃]^6- groups of Sr₃GaN₃ and Sr₆GaN₅ (1.938 Å, 1.895 Å, Park et al., 2003), Sr₄GaN₃O (1.880–1.921 Å, Mallinson et al., 2006) and LiBa₅GaN₃F₅ (1.896–1.945 Å, Hintze & Schnick, 2010). Ba1 atom is coordinated by two N1, one N2 and three O1 atoms, and Ba2 atom is by one N1, two N2 and three O1 atoms. N1 and N2 atoms are in seven-fold coordination sites of one Ga and six Ba atoms, and N3 atom is in the six-fold coordination site of one Ga and five Ba atoms. O1 atom is coordinated by seven Ba atoms. As shown in Fig. 2, O1 atoms are situated at the sites between [Ba₄GaN₃] slabs which are composed of triangular [GaN₃] groups and Ba atoms in the a–c plane.

Mallinson et al., (2006) calculated Madelung site potential and Madelung energy per formula of Sr₄GaN₃O for four models of O and N atom arrangement. They concluded the model with O atom located at the O1 site coordinated by only Sr atoms is the most stable structure because this model showed the smallest deviation of the site potentials in atom sites of the same species and the lowest energy. The site potentials and energy calculated by using EUTAX (O'Keeffe, 1992) and VESTA (Momma & Izumi, 2008) programs with the data of the present study are -17.12 – -17.87 V for Ba1–Ba4, -36.17 V for Ga1, 28.24 – 29.45 V for N1–N3, 16.86 V for O1, and -26,100 kJ/mol for Ba₄GaN₃O. The values of Ga, N and O sites were consistent with the site potentials reported for Sr₄GaN₃O (Ga: -35.01 V, N: 29.58 – 31.38 V, O: 17.36 V) (Mallinson et al., 2006). The difference between the Madelung energy per formula of Ba₄GaN₃O and the sum of Madelung energies of Ba₃N₂ derived by the theoretical calculation (-12,200 kJ/mol, Orhan et al., 2002), BaO (-3,500 kJ/mol, Taylor, 1984) and GaN (-10,500 kJ/mol, Paszkowicz et al., 2004) calculated from the crystal structure data is 0.4%.

Experimental top

Starting materials were pieces of Ba (Sigma-Aldrich, 99.99%), Ga (Rasa Industries, 99.99995%) and Na (Nippon Soda Co. Ltd., 99.95%), and powders of Si (Kojundo Chemical Laboratory, 99.999%) and NaN₃ (Toyo Kasei Kogyo Co. Ltd., 99.9%). In an Ar gas-filled glove box (O₂ < 1 ppm, H₂O < 1 ppm), Ba (1.00 mmol), Ga (0.25 mmol), Na (2.4 mmol), Si (0.50 mmol) and NaN₃ (1.2 mmol) were weighed and placed in a BN crucible (Showa Denko, 99.5%). The crucible was sealed in a stainless-steel tube. The sample was heated to 750°C in an electric furnace with a rate of 6°C min^-1. This temperature was maintained for 2 hours and lowered to 550°C with a cooling rate of -2.8°C min^-1. After that the sample was cooled to room temperature by shutting off the electric power to the furnace. The stainless-steel tube was cut and opened in the glove box, and the crucible was washed with liquid NH₃ (Japan Fine Products, >99.999%) to dissolve away Na. The details of the Na removing method have been described in the literature (Kowach et al., 1998). The initial objective was to synthesize a Ba–Ga–Si–N quaternary compound by the Na flux method, but the main product obtained was yellow transparent granular single crystals of Ba₃Ga₂N₄ (Yamane & DiSalvo, 1996). A small amount of red transparent platelet single crystals of Ba₄GaN₃O were included in the product.

Semi-quantitative elemental analysis of the red single crystals was carried out with an energy-dispersive X-ray detector (EDX, EDAX, Genesis) attached to a scanning electron microscope (SEM, Hitachi, S-4800). Ba:Ga molar ratio determined by the EDX analysis was 78:22 which was close to the ratio (4:1) of Ba₄GaN₃O. The oxygen was probably originated from the surface oxide layers of the starting materials. Since Ba₄GaN₃O is unstable in air, a single crystal was picked up from the product and sealed in glass capillaries in the glove box for XRD data collection.

The peaks of 2.25–2.54 e Å^-3 in the F_o–F_c map were observed at 0.88–0.96 Å distant from Ba1–Ba3 atoms. These large differences are probably a result of the cut-off effect of the Fourier synthesis.

Related literature top

For isotypic Sr₄GaN₃O, see: Mallinson et al. (2006). For the major phase in the product, Ba₃Ga₂N₄, see: Yamane & DiSalvo (1996). For compounds containing isolated trianglular planar [GaN₃]^6- nitridogallate anions, see: Park et al. (2003); Mallinson et al. (2006); Hintze & Schnick (2010).

Computing details top

Data collection: RAPID-AUTO (Rigaku Corporation, 2005); cell refinement: RAPID-AUTO (Rigaku Corporation, 2005); data reduction: RAPID-AUTO (Rigaku Corporation, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: VESTA (Momma & Izumi, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. The atomic arrangement around Ba and Ga atoms in the structure of Ba₄GaN₃O. Displacement ellipsoids are drawn at 70% probability. Symmetry codes: (i) x, -y + 1/2, z + 1/2; (ii) -x + 1/2, y + 1/2, z; (iii) x + 1/2, y, -z + 1/2; (iv) x + 1/2, -y + 1/2, -z; (v) -x, y + 1/2, -z + 1/2.
	Fig. 2. Crystal structure of Ba₄GaN₃O illustrated with Ga-centered N atom triangles.

Tetrabarium gallium trinitride oxide top

Crystal data top

Ba₄GaN₃O	F(000) = 2272
M_r = 677.11	D_x = 5.671 Mg m⁻³
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71075 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 11112 reflections
a = 7.8130 (3) Å	θ = 3.0–27.5°
b = 25.6453 (10) Å	µ = 22.84 mm⁻¹
c = 7.9162 (4) Å	T = 293 K
V = 1586.14 (12) Å³	Platelet, red
Z = 8	0.18 × 0.13 × 0.07 mm

Data collection top

Rigaku R-AXIS RAPID II diffractometer	1820 independent reflections
Radiation source: fine-focus sealed tube	1588 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.133
Detector resolution: 10.0 pixels mm^-1	θ_max = 27.5°, θ_min = 3.0°
ω scans	h = −9→10
Absorption correction: numerical (NUMABS; Higashi, 1999)	k = −33→33
T_min = 0.071, T_max = 0.411	l = −10→10
14273 measured reflections

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Primary atom site location: structure-invariant direct methods
R[F² > 2σ(F²)] = 0.043	Secondary atom site location: difference Fourier map
wR(F²) = 0.099	w = 1/[σ²(F_o²) + (0.P)² + 18.6031P] where P = (F_o² + 2F_c²)/3
S = 1.05	(Δ/σ)_max = 0.001
1820 reflections	Δρ_max = 2.54 e Å⁻³
82 parameters	Δρ_min = −1.72 e Å⁻³

Crystal data top

Ba₄GaN₃O	V = 1586.14 (12) Å³
M_r = 677.11	Z = 8
Orthorhombic, Pbca	Mo Kα radiation
a = 7.8130 (3) Å	µ = 22.84 mm⁻¹
b = 25.6453 (10) Å	T = 293 K
c = 7.9162 (4) Å	0.18 × 0.13 × 0.07 mm

Data collection top

Rigaku R-AXIS RAPID II diffractometer	1820 independent reflections
Absorption correction: numerical (NUMABS; Higashi, 1999)	1588 reflections with I > 2σ(I)
T_min = 0.071, T_max = 0.411	R_int = 0.133
14273 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.043	0 restraints
wR(F²) = 0.099	w = 1/[σ²(F_o²) + (0.P)² + 18.6031P] where P = (F_o² + 2F_c²)/3
S = 1.05	Δρ_max = 2.54 e Å⁻³
1820 reflections	Δρ_min = −1.72 e Å⁻³
82 parameters

Special details top

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	U_iso*/U_eq
Ba1	0.36690 (8)	0.42906 (2)	0.32613 (7)	0.02148 (18)
Ba2	0.03129 (8)	0.06166 (2)	0.16149 (7)	0.02055 (18)
Ba3	0.45621 (7)	0.26486 (2)	0.23802 (7)	0.02003 (18)
Ba4	0.20527 (8)	0.15269 (2)	0.46083 (7)	0.02310 (19)
Ga1	0.20637 (12)	0.17178 (4)	0.01682 (12)	0.0157 (2)
N1	0.0710 (11)	0.3685 (3)	0.3614 (11)	0.0246 (19)
N2	0.3630 (10)	0.1319 (3)	0.1492 (9)	0.0187 (17)
N3	0.1943 (10)	0.2448 (3)	0.0124 (9)	0.0169 (17)
O1	0.2416 (12)	0.0314 (4)	0.4918 (11)	0.049 (2)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Ba1	0.0234 (3)	0.0214 (4)	0.0196 (3)	0.0002 (2)	0.0046 (2)	0.0002 (2)
Ba2	0.0211 (3)	0.0211 (4)	0.0194 (3)	−0.0001 (2)	0.0009 (2)	−0.0004 (2)
Ba3	0.0152 (3)	0.0326 (4)	0.0123 (3)	0.0000 (2)	0.0001 (2)	0.0007 (2)
Ba4	0.0258 (3)	0.0226 (4)	0.0209 (3)	0.0000 (2)	0.0001 (2)	−0.0023 (2)
Ga1	0.0158 (5)	0.0183 (6)	0.0132 (5)	−0.0002 (4)	−0.0006 (4)	−0.0001 (4)
N1	0.026 (4)	0.019 (5)	0.029 (5)	0.011 (4)	−0.010 (4)	0.006 (3)
N2	0.022 (4)	0.020 (4)	0.015 (4)	0.006 (3)	−0.002 (3)	0.000 (3)
N3	0.022 (4)	0.011 (4)	0.018 (4)	−0.002 (3)	−0.002 (3)	−0.001 (3)
O1	0.053 (5)	0.052 (6)	0.041 (5)	−0.007 (5)	0.001 (4)	−0.010 (4)

Geometric parameters (Å, º) top

Ba1—N1ⁱ	2.675 (8)	Ba4—N1^viii	3.231 (9)
Ba1—N1	2.799 (9)	Ga1—N3	1.876 (8)
Ba1—N2ⁱⁱ	2.998 (7)	Ga1—N2	1.908 (8)
Ba1—O1ⁱⁱⁱ	2.999 (8)	Ga1—N1ⁱⁱⁱ	1.924 (8)
Ba1—O1^iv	3.054 (9)	Ga1—Ba3^ix	3.2450 (11)
Ba1—Ga1ⁱⁱ	3.2466 (12)	Ga1—Ba1ⁱⁱⁱ	3.2467 (12)
Ba2—O1^v	2.683 (9)	Ga1—Ba3ⁱⁱⁱ	3.3648 (11)
Ba2—N2^v	2.687 (8)	N1—Ga1ⁱⁱ	1.924 (8)
Ba2—N1ⁱⁱⁱ	2.991 (9)	N1—Ba1^v	2.675 (8)
Ba2—N2	3.158 (8)	N1—Ba3^v	2.914 (9)
Ba2—O1	3.184 (9)	N1—Ba2ⁱⁱ	2.991 (9)
Ba2—O1^vi	3.264 (10)	N1—Ba4^x	3.231 (9)
Ba2—Ga1	3.3405 (12)	N2—Ba2ⁱ	2.687 (8)
Ba3—N3^vii	2.730 (7)	N2—Ba4ⁱ	2.862 (8)
Ba3—N3ⁱ	2.762 (8)	N2—Ba1ⁱⁱⁱ	2.998 (7)
Ba3—N3	2.764 (7)	N3—Ba4ⁱⁱⁱ	2.661 (8)
Ba3—N1ⁱ	2.914 (9)	N3—Ba3^ix	2.730 (7)
Ba3—N3ⁱⁱ	2.994 (8)	N3—Ba3^v	2.762 (8)
Ba3—Ga1^vii	3.2450 (11)	N3—Ba3ⁱⁱⁱ	2.994 (8)
Ba3—Ga1ⁱⁱ	3.3647 (11)	O1—Ba2ⁱ	2.683 (9)
Ba4—N3ⁱⁱ	2.661 (8)	O1—Ba1ⁱⁱ	2.999 (8)
Ba4—N2	2.808 (7)	O1—Ba1^xi	3.054 (9)
Ba4—N2^v	2.862 (8)	O1—Ba2^xii	3.264 (10)
Ba4—O1	3.133 (10)

N1ⁱ—Ba1—N1	103.0 (3)	Ba4ⁱⁱⁱ—Ba3—Ba4^viii	109.76 (2)
N1ⁱ—Ba1—N2ⁱⁱ	100.2 (2)	Ga1ⁱ—Ba3—Ba4^viii	75.61 (2)
N1—Ba1—N2ⁱⁱ	67.5 (2)	N3^vii—Ba3—Ba4ⁱ	44.25 (16)
N1ⁱ—Ba1—O1ⁱⁱⁱ	84.3 (3)	N3ⁱ—Ba3—Ba4ⁱ	79.12 (16)
N1—Ba1—O1ⁱⁱⁱ	90.3 (2)	N3—Ba3—Ba4ⁱ	88.33 (16)
N2ⁱⁱ—Ba1—O1ⁱⁱⁱ	157.8 (2)	N1ⁱ—Ba3—Ba4ⁱ	114.81 (15)
N1ⁱ—Ba1—O1^iv	154.5 (3)	N3ⁱⁱ—Ba3—Ba4ⁱ	125.84 (15)
N1—Ba1—O1^iv	101.8 (3)	Ga1^vii—Ba3—Ba4ⁱ	79.26 (2)
N2ⁱⁱ—Ba1—O1^iv	94.5 (2)	Ga1ⁱⁱ—Ba3—Ba4ⁱ	158.61 (3)
O1ⁱⁱⁱ—Ba1—O1^iv	89.88 (12)	Ga1—Ba3—Ba4ⁱ	64.48 (2)
N1ⁱ—Ba1—Ga1ⁱⁱ	91.49 (19)	Ba4ⁱⁱⁱ—Ba3—Ba4ⁱ	117.798 (17)
N1—Ba1—Ga1ⁱⁱ	36.16 (16)	Ga1ⁱ—Ba3—Ba4ⁱ	56.77 (2)
N2ⁱⁱ—Ba1—Ga1ⁱⁱ	35.30 (15)	Ba4^viii—Ba3—Ba4ⁱ	115.14 (2)
O1ⁱⁱⁱ—Ba1—Ga1ⁱⁱ	123.61 (19)	N3ⁱⁱ—Ba4—N2	109.6 (2)
O1^iv—Ba1—Ga1ⁱⁱ	112.20 (18)	N3ⁱⁱ—Ba4—N2^v	101.6 (2)
N1ⁱ—Ba1—Ba2^iv	102.02 (19)	N2—Ba4—N2^v	96.16 (14)
N1—Ba1—Ba2^iv	135.83 (16)	N3ⁱⁱ—Ba4—O1	166.3 (2)
N2ⁱⁱ—Ba1—Ba2^iv	140.93 (15)	N2—Ba4—O1	80.8 (2)
O1ⁱⁱⁱ—Ba1—Ba2^iv	56.82 (19)	N2^v—Ba4—O1	85.6 (2)
O1^iv—Ba1—Ba2^iv	54.92 (18)	N3ⁱⁱ—Ba4—N1^viii	97.3 (2)
Ga1ⁱⁱ—Ba1—Ba2^iv	166.34 (3)	N2—Ba4—N1^viii	87.9 (2)
N1ⁱ—Ba1—Ba2ⁱⁱ	148.09 (19)	N2^v—Ba4—N1^viii	158.0 (2)
N1—Ba1—Ba2ⁱⁱ	52.06 (18)	O1—Ba4—N1^viii	73.7 (2)
N2ⁱⁱ—Ba1—Ba2ⁱⁱ	54.58 (15)	N3ⁱⁱ—Ba4—Ga1	90.91 (16)
O1ⁱⁱⁱ—Ba1—Ba2ⁱⁱ	112.10 (18)	N2—Ba4—Ga1	32.35 (15)
O1^iv—Ba1—Ba2ⁱⁱ	56.35 (18)	N2^v—Ba4—Ga1	74.12 (15)
Ga1ⁱⁱ—Ba1—Ba2ⁱⁱ	56.61 (2)	O1—Ba4—Ga1	102.37 (15)
Ba2^iv—Ba1—Ba2ⁱⁱ	109.870 (18)	N1^viii—Ba4—Ga1	116.90 (14)
N1ⁱ—Ba1—Ba4^viii	60.51 (19)	N3ⁱⁱ—Ba4—Ba2ⁱ	134.97 (17)
N1—Ba1—Ba4^viii	103.06 (16)	N2—Ba4—Ba2ⁱ	47.79 (16)
N2ⁱⁱ—Ba1—Ba4^viii	48.37 (15)	N2^v—Ba4—Ba2ⁱ	117.38 (16)
O1ⁱⁱⁱ—Ba1—Ba4^viii	144.23 (18)	O1—Ba4—Ba2ⁱ	46.44 (17)
O1^iv—Ba1—Ba4^viii	118.70 (17)	N1^viii—Ba4—Ba2ⁱ	51.70 (15)
Ga1ⁱⁱ—Ba1—Ba4^viii	67.67 (2)	Ga1—Ba4—Ba2ⁱ	79.68 (2)
Ba2^iv—Ba1—Ba4^viii	120.92 (2)	N3ⁱⁱ—Ba4—Ba2	136.94 (16)
Ba2ⁱⁱ—Ba1—Ba4^viii	102.089 (19)	N2—Ba4—Ba2	57.57 (17)
N1ⁱ—Ba1—Ba4ⁱⁱⁱ	56.90 (19)	N2^v—Ba4—Ba2	47.55 (15)
N1—Ba1—Ba4ⁱⁱⁱ	59.59 (18)	O1—Ba4—Ba2	56.00 (16)
N2ⁱⁱ—Ba1—Ba4ⁱⁱⁱ	111.04 (15)	N1^viii—Ba4—Ba2	120.82 (16)
O1ⁱⁱⁱ—Ba1—Ba4ⁱⁱⁱ	53.45 (19)	Ga1—Ba4—Ba2	55.77 (2)
O1^iv—Ba1—Ba4ⁱⁱⁱ	135.30 (17)	Ba2ⁱ—Ba4—Ba2	70.604 (15)
Ga1ⁱⁱ—Ba1—Ba4ⁱⁱⁱ	77.60 (2)	N3ⁱⁱ—Ba4—Ba3ⁱⁱ	49.31 (16)
Ba2^iv—Ba1—Ba4ⁱⁱⁱ	108.003 (19)	N2—Ba4—Ba3ⁱⁱ	113.90 (17)
Ba2ⁱⁱ—Ba1—Ba4ⁱⁱⁱ	110.09 (2)	N2^v—Ba4—Ba3ⁱⁱ	142.97 (15)
Ba4^viii—Ba1—Ba4ⁱⁱⁱ	105.50 (2)	O1—Ba4—Ba3ⁱⁱ	118.88 (16)
N1ⁱ—Ba1—Ba2^vii	47.19 (19)	N1^viii—Ba4—Ba3ⁱⁱ	49.91 (15)
N1—Ba1—Ba2^vii	112.78 (17)	Ga1—Ba4—Ba3ⁱⁱ	121.19 (3)
N2ⁱⁱ—Ba1—Ba2^vii	147.32 (16)	Ba2ⁱ—Ba4—Ba3ⁱⁱ	99.15 (2)
O1ⁱⁱⁱ—Ba1—Ba2^vii	41.16 (18)	Ba2—Ba4—Ba3ⁱⁱ	169.46 (2)
O1^iv—Ba1—Ba2^vii	116.36 (17)	N3ⁱⁱ—Ba4—Ba3^x	47.62 (16)
Ga1ⁱⁱ—Ba1—Ba2^vii	127.49 (3)	N2—Ba4—Ba3^x	153.75 (16)
Ba2^iv—Ba1—Ba2^vii	63.146 (17)	N2^v—Ba4—Ba3^x	79.21 (15)
Ba2ⁱⁱ—Ba1—Ba2^vii	152.86 (2)	O1—Ba4—Ba3^x	124.02 (16)
Ba4^viii—Ba1—Ba2^vii	103.594 (19)	N1^viii—Ba4—Ba3^x	106.15 (15)
Ba4ⁱⁱⁱ—Ba1—Ba2^vii	54.148 (15)	Ga1—Ba4—Ba3^x	123.74 (2)
N1ⁱ—Ba1—Ba1ⁱ	42.85 (19)	Ba2ⁱ—Ba4—Ba3^x	155.60 (2)
N1—Ba1—Ba1ⁱ	144.95 (17)	Ba2—Ba4—Ba3^x	126.28 (2)
N2ⁱⁱ—Ba1—Ba1ⁱ	105.14 (15)	Ba3ⁱⁱ—Ba4—Ba3^x	64.206 (12)
O1ⁱⁱⁱ—Ba1—Ba1ⁱ	92.97 (19)	N3ⁱⁱ—Ba4—Ba1^x	117.25 (17)
O1^iv—Ba1—Ba1ⁱ	113.06 (19)	N2—Ba4—Ba1^x	126.50 (17)
Ga1ⁱⁱ—Ba1—Ba1ⁱ	120.41 (2)	N2^v—Ba4—Ba1^x	51.53 (15)
Ba2^iv—Ba1—Ba1ⁱ	72.121 (14)	O1—Ba4—Ba1^x	58.44 (17)
Ba2ⁱⁱ—Ba1—Ba1ⁱ	151.58 (2)	N1^viii—Ba4—Ba1^x	109.36 (14)
Ba4^viii—Ba1—Ba1ⁱ	57.460 (13)	Ga1—Ba4—Ba1^x	121.41 (2)
Ba4ⁱⁱⁱ—Ba1—Ba1ⁱ	95.36 (2)	Ba2ⁱ—Ba4—Ba1^x	104.86 (2)
Ba2^vii—Ba1—Ba1ⁱ	54.518 (17)	Ba2—Ba4—Ba1^x	70.646 (17)
O1^v—Ba2—N2^v	91.9 (3)	Ba3ⁱⁱ—Ba4—Ba1^x	115.65 (2)
O1^v—Ba2—N1ⁱⁱⁱ	84.3 (2)	Ba3^x—Ba4—Ba1^x	70.370 (17)
N2^v—Ba2—N1ⁱⁱⁱ	95.3 (2)	N3ⁱⁱ—Ba4—Ba1ⁱⁱ	116.11 (16)
O1^v—Ba2—N2	147.5 (2)	N2—Ba4—Ba1ⁱⁱ	114.79 (16)
N2^v—Ba2—N2	92.1 (2)	N2^v—Ba4—Ba1ⁱⁱ	116.15 (16)
N1ⁱⁱⁱ—Ba2—N2	63.2 (2)	O1—Ba4—Ba1ⁱⁱ	50.26 (16)
O1^v—Ba2—O1	137.4 (3)	N1^viii—Ba4—Ba1ⁱⁱ	43.92 (14)
N2^v—Ba2—O1	87.6 (2)	Ga1—Ba4—Ba1ⁱⁱ	146.26 (3)
N1ⁱⁱⁱ—Ba2—O1	138.1 (2)	Ba2ⁱ—Ba4—Ba1ⁱⁱ	67.004 (17)
N2—Ba2—O1	75.0 (2)	Ba2—Ba4—Ba1ⁱⁱ	105.66 (2)
O1^v—Ba2—O1^vi	93.5 (3)	Ba3ⁱⁱ—Ba4—Ba1ⁱⁱ	71.359 (18)
N2^v—Ba2—O1^vi	170.4 (2)	Ba3^x—Ba4—Ba1ⁱⁱ	89.987 (19)
N1ⁱⁱⁱ—Ba2—O1^vi	93.1 (2)	Ba1^x—Ba4—Ba1ⁱⁱ	65.465 (13)
N2—Ba2—O1^vi	87.6 (2)	N3—Ga1—N2	125.3 (3)
O1—Ba2—O1^vi	83.07 (11)	N3—Ga1—N1ⁱⁱⁱ	119.8 (3)
O1^v—Ba2—Ga1	115.78 (19)	N2—Ga1—N1ⁱⁱⁱ	114.6 (4)
N2^v—Ba2—Ga1	79.89 (17)	N3—Ga1—Ba3^ix	57.2 (2)
N1ⁱⁱⁱ—Ba2—Ga1	34.82 (15)	N2—Ga1—Ba3^ix	174.9 (2)
N2—Ba2—Ga1	34.00 (14)	N1ⁱⁱⁱ—Ga1—Ba3^ix	62.6 (3)
O1—Ba2—Ga1	106.04 (17)	N3—Ga1—Ba1ⁱⁱⁱ	143.7 (2)
O1^vi—Ba2—Ga1	104.74 (16)	N2—Ga1—Ba1ⁱⁱⁱ	65.2 (2)
O1^v—Ba2—Ba4^v	57.8 (2)	N1ⁱⁱⁱ—Ga1—Ba1ⁱⁱⁱ	59.1 (3)
N2^v—Ba2—Ba4^v	50.72 (16)	Ba3^ix—Ga1—Ba1ⁱⁱⁱ	110.03 (3)
N1ⁱⁱⁱ—Ba2—Ba4^v	57.98 (17)	N3—Ga1—Ba2	146.1 (2)
N2—Ba2—Ba4^v	101.71 (14)	N2—Ga1—Ba2	67.8 (2)
O1—Ba2—Ba4^v	138.28 (17)	N1ⁱⁱⁱ—Ga1—Ba2	62.6 (3)
O1^vi—Ba2—Ba4^v	138.65 (15)	Ba3^ix—Ga1—Ba2	112.94 (3)
Ga1—Ba2—Ba4^v	69.40 (2)	Ba1ⁱⁱⁱ—Ga1—Ba2	69.15 (3)
O1^v—Ba2—Ba4	143.6 (2)	N3—Ga1—Ba3ⁱⁱⁱ	62.3 (2)
N2^v—Ba2—Ba4	51.81 (17)	N2—Ga1—Ba3ⁱⁱⁱ	104.3 (2)
N1ⁱⁱⁱ—Ba2—Ba4	95.48 (15)	N1ⁱⁱⁱ—Ga1—Ba3ⁱⁱⁱ	99.1 (3)
N2—Ba2—Ba4	48.63 (13)	Ba3^ix—Ga1—Ba3ⁱⁱⁱ	72.53 (2)
O1—Ba2—Ba4	54.66 (17)	Ba1ⁱⁱⁱ—Ga1—Ba3ⁱⁱⁱ	81.70 (3)
O1^vi—Ba2—Ba4	122.74 (17)	Ba2—Ga1—Ba3ⁱⁱⁱ	150.54 (4)
Ga1—Ba2—Ba4	61.44 (2)	N3—Ga1—Ba3	50.6 (2)
Ba4^v—Ba2—Ba4	91.37 (2)	N2—Ga1—Ba3	74.7 (2)
O1^v—Ba2—Ba1^xi	94.3 (2)	N1ⁱⁱⁱ—Ga1—Ba3	168.6 (3)
N2^v—Ba2—Ba1^xi	121.42 (16)	Ba3^ix—Ga1—Ba3	107.55 (3)
N1ⁱⁱⁱ—Ba2—Ba1^xi	143.29 (17)	Ba1ⁱⁱⁱ—Ga1—Ba3	123.58 (3)
N2—Ba2—Ba1^xi	110.87 (14)	Ba2—Ga1—Ba3	128.70 (3)
O1—Ba2—Ba1^xi	51.72 (17)	Ba3ⁱⁱⁱ—Ga1—Ba3	71.31 (2)
O1^vi—Ba2—Ba1^xi	50.26 (15)	N3—Ga1—Ba4	99.0 (2)
Ga1—Ba2—Ba1^xi	143.49 (3)	N2—Ga1—Ba4	51.9 (2)
Ba4^v—Ba2—Ba1^xi	147.07 (2)	N1ⁱⁱⁱ—Ga1—Ba4	123.9 (3)
Ba4—Ba2—Ba1^xi	106.34 (2)	Ba3^ix—Ga1—Ba4	133.11 (3)
O1^v—Ba2—Ba1ⁱⁱⁱ	106.80 (19)	Ba1ⁱⁱⁱ—Ga1—Ba4	110.58 (3)
N2^v—Ba2—Ba1ⁱⁱⁱ	134.13 (17)	Ba2—Ga1—Ba4	62.79 (2)
N1ⁱⁱⁱ—Ba2—Ba1ⁱⁱⁱ	47.56 (17)	Ba3ⁱⁱⁱ—Ga1—Ba4	135.86 (3)
N2—Ba2—Ba1ⁱⁱⁱ	50.68 (13)	Ba3—Ga1—Ba4	66.74 (2)
O1—Ba2—Ba1ⁱⁱⁱ	103.69 (17)	N3—Ga1—Ba3^v	47.9 (2)
O1^vi—Ba2—Ba1ⁱⁱⁱ	51.16 (15)	N2—Ga1—Ba3^v	113.7 (2)
Ga1—Ba2—Ba1ⁱⁱⁱ	54.24 (2)	N1ⁱⁱⁱ—Ga1—Ba3^v	113.4 (3)
Ba4^v—Ba2—Ba1ⁱⁱⁱ	105.36 (2)	Ba3^ix—Ga1—Ba3^v	71.35 (2)
Ba4—Ba2—Ba1ⁱⁱⁱ	99.30 (2)	Ba1ⁱⁱⁱ—Ga1—Ba3^v	167.54 (4)
Ba1^xi—Ba2—Ba1ⁱⁱⁱ	99.012 (17)	Ba2—Ga1—Ba3^v	98.71 (3)
O1^v—Ba2—Ba1^ix	47.36 (18)	Ba3ⁱⁱⁱ—Ga1—Ba3^v	110.13 (3)
N2^v—Ba2—Ba1^ix	109.56 (16)	Ba3—Ga1—Ba3^v	65.886 (19)
N1ⁱⁱⁱ—Ba2—Ba1^ix	41.01 (14)	Ba4—Ga1—Ba3^v	64.00 (2)
N2—Ba2—Ba1^ix	101.32 (13)	Ga1ⁱⁱ—N1—Ba1^v	173.9 (5)
O1—Ba2—Ba1^ix	162.69 (17)	Ga1ⁱⁱ—N1—Ba1	84.7 (3)
O1^vi—Ba2—Ba1^ix	79.87 (15)	Ba1^v—N1—Ba1	96.6 (3)
Ga1—Ba2—Ba1^ix	75.82 (2)	Ga1ⁱⁱ—N1—Ba3^v	81.5 (3)
Ba4^v—Ba2—Ba1^ix	58.845 (16)	Ba1^v—N1—Ba3^v	101.3 (3)
Ba4—Ba2—Ba1^ix	134.90 (2)	Ba1—N1—Ba3^v	137.2 (3)
Ba1^xi—Ba2—Ba1^ix	116.853 (17)	Ga1ⁱⁱ—N1—Ba2ⁱⁱ	82.6 (3)
Ba1ⁱⁱⁱ—Ba2—Ba1^ix	62.918 (10)	Ba1^v—N1—Ba2ⁱⁱ	91.8 (2)
N3^vii—Ba3—N3ⁱ	92.5 (2)	Ba1—N1—Ba2ⁱⁱ	80.4 (2)
N3^vii—Ba3—N3	91.05 (3)	Ba3^v—N1—Ba2ⁱⁱ	136.8 (3)
N3ⁱ—Ba3—N3	157.9 (3)	Ga1ⁱⁱ—N1—Ba4^x	96.7 (3)
N3^vii—Ba3—N1ⁱ	71.2 (2)	Ba1^v—N1—Ba4^x	79.2 (2)
N3ⁱ—Ba3—N1ⁱ	98.9 (2)	Ba1—N1—Ba4^x	150.1 (3)
N3—Ba3—N1ⁱ	102.9 (2)	Ba3^v—N1—Ba4^x	72.1 (2)
N3^vii—Ba3—N3ⁱⁱ	170.0 (3)	Ba2ⁱⁱ—N1—Ba4^x	70.32 (19)
N3ⁱ—Ba3—N3ⁱⁱ	85.75 (3)	Ga1—N2—Ba2ⁱ	168.3 (4)
N3—Ba3—N3ⁱⁱ	87.0 (2)	Ga1—N2—Ba4	95.7 (3)
N1ⁱ—Ba3—N3ⁱⁱ	118.8 (2)	Ba2ⁱ—N2—Ba4	81.5 (2)
N3^vii—Ba3—Ga1^vii	35.28 (16)	Ga1—N2—Ba4ⁱ	109.4 (3)
N3ⁱ—Ba3—Ga1^vii	97.59 (15)	Ba2ⁱ—N2—Ba4ⁱ	80.6 (2)
N3—Ba3—Ga1^vii	97.89 (16)	Ba4—N2—Ba4ⁱ	130.0 (3)
N1ⁱ—Ba3—Ga1^vii	35.89 (15)	Ga1—N2—Ba1ⁱⁱⁱ	79.5 (2)
N3ⁱⁱ—Ba3—Ga1^vii	154.71 (15)	Ba2ⁱ—N2—Ba1ⁱⁱⁱ	96.9 (2)
N3^vii—Ba3—Ga1ⁱⁱ	156.30 (16)	Ba4—N2—Ba1ⁱⁱⁱ	148.5 (3)
N3ⁱ—Ba3—Ga1ⁱⁱ	90.65 (16)	Ba4ⁱ—N2—Ba1ⁱⁱⁱ	80.09 (19)
N3—Ba3—Ga1ⁱⁱ	94.83 (16)	Ga1—N2—Ba2	78.2 (3)
N1ⁱ—Ba3—Ga1ⁱⁱ	85.14 (15)	Ba2ⁱ—N2—Ba2	90.1 (2)
N3ⁱⁱ—Ba3—Ga1ⁱⁱ	33.68 (15)	Ba4—N2—Ba2	73.80 (18)
Ga1^vii—Ba3—Ga1ⁱⁱ	121.03 (4)	Ba4ⁱ—N2—Ba2	151.9 (3)
N3^vii—Ba3—Ga1	87.43 (16)	Ba1ⁱⁱⁱ—N2—Ba2	74.74 (18)
N3ⁱ—Ba3—Ga1	126.79 (16)	Ga1—N3—Ba4ⁱⁱⁱ	170.9 (4)
N3—Ba3—Ga1	31.61 (16)	Ga1—N3—Ba3^ix	87.5 (3)
N1ⁱ—Ba3—Ga1	130.55 (17)	Ba4ⁱⁱⁱ—N3—Ba3^ix	90.0 (2)
N3ⁱⁱ—Ba3—Ga1	85.77 (15)	Ga1—N3—Ba3^v	101.9 (3)
Ga1^vii—Ba3—Ga1	111.20 (2)	Ba4ⁱⁱⁱ—N3—Ba3^v	87.0 (2)
Ga1ⁱⁱ—Ba3—Ga1	109.24 (3)	Ba3^ix—N3—Ba3^v	94.4 (2)
N3^vii—Ba3—Ba4ⁱⁱⁱ	88.97 (16)	Ga1—N3—Ba3	97.8 (3)
N3ⁱ—Ba3—Ba4ⁱⁱⁱ	154.98 (16)	Ba4ⁱⁱⁱ—N3—Ba3	83.8 (2)
N3—Ba3—Ba4ⁱⁱⁱ	46.89 (16)	Ba3^ix—N3—Ba3	172.1 (3)
N1ⁱ—Ba3—Ba4ⁱⁱⁱ	58.03 (17)	Ba3^v—N3—Ba3	90.1 (2)
N3ⁱⁱ—Ba3—Ba4ⁱⁱⁱ	96.78 (14)	Ga1—N3—Ba3ⁱⁱⁱ	84.1 (3)
Ga1^vii—Ba3—Ba4ⁱⁱⁱ	69.95 (2)	Ba4ⁱⁱⁱ—N3—Ba3ⁱⁱⁱ	87.1 (2)
Ga1ⁱⁱ—Ba3—Ba4ⁱⁱⁱ	78.55 (2)	Ba3^ix—N3—Ba3ⁱⁱⁱ	86.1 (2)
Ga1—Ba3—Ba4ⁱⁱⁱ	78.22 (2)	Ba3^v—N3—Ba3ⁱⁱⁱ	174.0 (3)
N3^vii—Ba3—Ga1ⁱ	87.80 (16)	Ba3—N3—Ba3ⁱⁱⁱ	88.8 (2)
N3ⁱ—Ba3—Ga1ⁱ	30.24 (16)	Ba2ⁱ—O1—Ba1ⁱⁱ	91.5 (3)
N3—Ba3—Ga1ⁱ	128.27 (16)	Ba2ⁱ—O1—Ba1^xi	106.8 (3)
N1ⁱ—Ba3—Ga1ⁱ	125.19 (17)	Ba1ⁱⁱ—O1—Ba1^xi	139.5 (3)
N3ⁱⁱ—Ba3—Ga1ⁱ	85.74 (14)	Ba2ⁱ—O1—Ba4	75.8 (2)
Ga1^vii—Ba3—Ga1ⁱ	109.63 (3)	Ba1ⁱⁱ—O1—Ba4	76.3 (2)
Ga1ⁱⁱ—Ba3—Ga1ⁱ	106.15 (2)	Ba1^xi—O1—Ba4	142.6 (3)
Ga1—Ba3—Ga1ⁱ	96.74 (3)	Ba2ⁱ—O1—Ba2	89.6 (2)
Ba4ⁱⁱⁱ—Ba3—Ga1ⁱ	174.14 (3)	Ba1ⁱⁱ—O1—Ba2	144.2 (3)
N3^vii—Ba3—Ba4^viii	99.21 (16)	Ba1^xi—O1—Ba2	73.36 (19)
N3ⁱ—Ba3—Ba4^viii	45.37 (16)	Ba4—O1—Ba2	69.3 (2)
N3—Ba3—Ba4^viii	154.63 (16)	Ba2ⁱ—O1—Ba2^xii	86.5 (3)
N1ⁱ—Ba3—Ba4^viii	59.70 (17)	Ba1ⁱⁱ—O1—Ba2^xii	72.9 (2)
N3ⁱⁱ—Ba3—Ba4^viii	86.56 (15)	Ba1^xi—O1—Ba2^xii	72.5 (2)
Ga1^vii—Ba3—Ba4^viii	78.43 (2)	Ba4—O1—Ba2^xii	143.9 (3)
Ga1ⁱⁱ—Ba3—Ba4^viii	67.05 (2)	Ba2—O1—Ba2^xii	142.8 (3)
Ga1—Ba3—Ba4^viii	169.55 (3)

Symmetry codes: (i) x+1/2, y, −z+1/2; (ii) x, −y+1/2, z+1/2; (iii) x, −y+1/2, z−1/2; (iv) −x+1/2, y+1/2, z; (v) x−1/2, y, −z+1/2; (vi) −x+1/2, −y, z−1/2; (vii) x+1/2, −y+1/2, −z; (viii) x+1/2, −y+1/2, −z+1; (ix) x−1/2, −y+1/2, −z; (x) x−1/2, −y+1/2, −z+1; (xi) −x+1/2, y−1/2, z; (xii) −x+1/2, −y, z+1/2.

Selected geometric parameters (Å, º) top

Ba1—N1ⁱ	2.675 (8)	Ba3—N3ⁱ	2.762 (8)
Ba1—N1	2.799 (9)	Ba3—N3	2.764 (7)
Ba1—N2ⁱⁱ	2.998 (7)	Ba3—N1ⁱ	2.914 (9)
Ba1—O1ⁱⁱⁱ	2.999 (8)	Ba3—N3ⁱⁱ	2.994 (8)
Ba1—O1^iv	3.054 (9)	Ba4—N3ⁱⁱ	2.661 (8)
Ba2—O1^v	2.683 (9)	Ba4—N2	2.808 (7)
Ba2—N2^v	2.687 (8)	Ba4—N2^v	2.862 (8)
Ba2—N1ⁱⁱⁱ	2.991 (9)	Ba4—O1	3.133 (10)
Ba2—N2	3.158 (8)	Ba4—N1^viii	3.231 (9)
Ba2—O1	3.184 (9)	Ga1—N3	1.876 (8)
Ba2—O1^vi	3.264 (10)	Ga1—N2	1.908 (8)
Ba3—N3^vii	2.730 (7)	Ga1—N1ⁱⁱⁱ	1.924 (8)

N3—Ga1—N2	125.3 (3)	N2—Ga1—N1ⁱⁱⁱ	114.6 (4)
N3—Ga1—N1ⁱⁱⁱ	119.8 (3)

Acknowledgements

This work was supported in part by a Grant-in-Aid for Scientific Resarch (C) (No. 25420701, 2013) from the Ministry of Education, Culture, Sports and Technology (MEXT), Japan.

References

Higashi, T. (1999). NUMABS. Rigaku Corporation, Tokyo, Japan. Google Scholar
Hintze, F. & Schnick, W. (2010). Solid State Sci. 12, 1368–1373. Web of Science CrossRef CAS Google Scholar
Kowach, G. R., Lin, H. Y. & DiSalvo, F. J. (1998). J. Solid State Chem. 141, 1–9. Web of Science CrossRef CAS Google Scholar
Mallinson, P. M., Gál, Z. A. & Clarke, S. J. (2006). Inorg. Chem. 45, 419–423. Web of Science CrossRef PubMed CAS Google Scholar
Momma, K. & Izumi, F. (2008). J. Appl. Cryst. 41, 653–658. Web of Science CrossRef CAS IUCr Journals Google Scholar
O'Keeffe, M. (1992). EUTAX. Arizona State University, USA. Google Scholar
Orhan, E., Jobic, S., Brec, R., Marchand, R. & Saillard, J.-Y. (2002). J. Mater. Chem. 12, 2475–2479. Web of Science CrossRef CAS Google Scholar
Park, D. G., Gál, Z. A. & DiSalvo, F. J. (2003). Inorg. Chem. 42, 1779–1785. Web of Science CrossRef PubMed CAS Google Scholar
Paszkowicz, W., Podsiadło, S. & Minikayev, R. (2004). J. Alloys Compd, 382, 100–106. Web of Science CrossRef CAS Google Scholar
Rigaku Corporation (2005). RAPID-AUTO. Rigaku Corporation, Tokyo, Japan. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Taylor, D. (1984). Trans. Br. Ceram. Soc. 83, 5–9. Google Scholar
Yamane, H. & DiSalvo, F. J. (1996). Acta Cryst. C52, 760–761. CrossRef CAS Web of Science IUCr Journals Google Scholar