Dirubidium digallium oxide bis­(ortho­borate)

Smith, R.W.; Hu, C.; DeSpain, C.D.

doi:10.1107/S1600536808005783

inorganic compounds

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Volume 64| Part 4| April 2008| Page i23

doi:10.1107/S1600536808005783

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Dirubidium digallium oxide bis(orthoborate)

Robert W. Smith,^a ^* Chunhua Hu ^b and Christopher D. DeSpain ^a

^aDepartment of Chemistry, University of Nebraska at Omaha, Omaha, NE 68182-0109, USA, and ^bNebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, NE 68588-0304, USA
^*Correspondence e-mail: robertsmith@mail.unomaha.edu

(Received 8 February 2008; accepted 29 February 2008; online 7 March 2008)

The title compound, Rb₂Ga₂O(BO₃)₂, is part of the homologous series A₂Ga₂O(BO₃)₂ (A = Na, K, Rb and Cs). The structure contains pairs of gallium-centered tetrahedra connected through a shared oxygen vertex. Orthoborate triangles connect the basal vertices of the tetrahedra, forming a three-dimensional network with voids occupied by rubidium ions.

Related literature

For related literature, see: Chen et al. (2004 ); Corbel & Leblanc (2000 ); Smith (1995 , 1997 ).

Experimental

Crystal data

Rb₂Ga₂O(BO₃)₂
M_r = 444.00
Monoclinic, P 2₁ /c
a = 8.8115 (18) Å
b = 7.7224 (16) Å
c = 11.997 (3) Å
β = 104.246 (4)°
V = 791.3 (3) Å³
Z = 4
Mo Kα radiation
μ = 19.03 mm⁻¹
T = 297 (2) K
0.23 × 0.21 × 0.19 mm

Data collection

Bruker SMART APEX CCD diffractometer
Absorption correction: numerical (SADABS; Sheldrick, 2003 ) T_min = 0.118, T_max = 0.429
8611 measured reflections
1568 independent reflections
1151 reflections with I > 2σ(I)
R_int = 0.093

Refinement

R[F² > 2σ(F²)] = 0.037
wR(F²) = 0.091
S = 1.05
1568 reflections
118 parameters
Δρ_max = 1.28 e Å⁻³
Δρ_min = −0.90 e Å⁻³

Table 1
Selected geometric parameters (Å, °)

Ga1—O3ⁱ	1.834 (5)
Ga1—O4ⁱⁱ	1.834 (5)
Ga1—O6	1.831 (5)
Ga1—O7ⁱⁱⁱ	1.790 (5)
Ga2—O1	1.840 (5)
Ga2—O2ⁱⁱⁱ	1.838 (5)
Ga2—O5^iv	1.832 (5)
Ga2—O7	1.810 (5)
B1—O1	1.376 (10)
B1—O2^v	1.370 (10)
B1—O3	1.358 (10)
B2—O4	1.366 (9)
B2—O5	1.395 (9)
B2—O6ⁱⁱⁱ	1.341 (10)

O7ⁱⁱⁱ—Ga1—O6	110.8 (2)
O7ⁱⁱⁱ—Ga1—O4ⁱⁱ	110.4 (2)
O6—Ga1—O4ⁱⁱ	114.5 (2)
O7ⁱⁱⁱ—Ga1—O3ⁱ	110.4 (2)
O6—Ga1—O3ⁱ	105.7 (2)
O4ⁱⁱ—Ga1—O3ⁱ	104.8 (2)
O7—Ga2—O5^iv	109.3 (2)
O7—Ga2—O2ⁱⁱⁱ	109.5 (2)
O5^iv—Ga2—O2ⁱⁱⁱ	110.6 (2)
O7—Ga2—O1	112.5 (2)
O5^iv—Ga2—O1	109.3 (2)
O2ⁱⁱⁱ—Ga2—O1	105.7 (2)
O3—B1—O2^v	119.4 (7)
O3—B1—O1	117.8 (8)
O2^v—B1—O1	122.7 (7)
O6ⁱⁱⁱ—B2—O4	124.7 (7)
O6ⁱⁱⁱ—B2—O5	116.3 (7)
O4—B2—O5	119.0 (7)
Symmetry codes: (i) $[x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ ; (ii) x+1, y, z; (iii) -x+1, -y, -z+1; (iv) $[x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ ; (v) x, y, z+1.

Data collection: SMART (Bruker, 2005 ); cell refinement: SAINT-Plus (Bruker, 2003 ); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: DIAMOND (Brandenburg & Putz, 2007 ); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808005783/mg2048sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808005783/mg2048Isup2.hkl

checkCIF report

Comment top

Complex metal borates adopt various structure types that result from the many possible geometric arrangements formed by metal-centered polyhedra and borate anions, which can be either three- or four-coordinate. They are also of interest as nonlinear optical materials, such as β-BaB₂O₄, LiB₃O₅, and YAl₃(BO₃)₄ (Chen et al., 2004). For these reasons, we have examined the phase diagrams of alkali metal gallium borates and have determined the crystal structures of some of the materials discovered. The homologous series A₂Ga₂O(BO₃)₂ (A = Na, K, Rb, Cs) is a portion of the new compounds discovered to date. In each, pairs of gallium-centered tetrahedra are connected through a shared oxygen vertex, and the tetrahedral basal planes are connected through shared oxygen vertices with triangular orthoborate anions. Depending on the size of the alkali metal ions, which occupy channels or spaces within the three-dimensional network, the compounds crystallize in different space groups: P31c for the Na member (Corbel & Leblanc, 2000), P321 for the K member (Smith et al., 1997), and P2₁/c for the Cs member (Smith, 1995), which is isotypic with the Rb compound reported herein (Fig. 1).

Related literature top

For related literature, see: Chen et al. (2004); Corbel & Leblanc (2000); Smith (1995,1997).

Experimental top

Powders of Rb₂Ga₂O(BO₃)₂ were prepared from stoichiometric mixtures of RbNO₃, Ga(NO₃)₃, and H₃BO₃, which were decomposed in alumina crucibles at 300 °C and then heated to 500 °C at 50 °C increments, with a soak of several hours at each temperature and intermediate grinding between each soak period. Crystals were grown in a platinum dish from a 1:1 molar mixture of the prepared powder in the presence of Rb₃BO₃ flux. The mixture was heated to 700 °C and cooled at 10 °C/hour to room temperature, and a single-crystal was cut from the crystal mass for subsequent X-ray diffraction analysis.

Computing details top

Data collection: SMART (Bruker, 2005); cell refinement: SAINT-Plus (Bruker, 2003); data reduction: SAINT-Plus (Bruker, 2003); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Putz, 2007); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

Fig. 1. View of the unit cell along the b axis. Displacement ellipsoids are drawn at the 50% probability level.

dirubidium digallium oxide bis(orthoborate) top

Crystal data top

Rb₂Ga₂O(BO₃)₂	F(000) = 808
M_r = 444.00	D_x = 3.727 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 1660 reflections
a = 8.8115 (18) Å	θ = 3.7–25.7°
b = 7.7224 (16) Å	µ = 19.03 mm⁻¹
c = 11.997 (3) Å	T = 297 K
β = 104.246 (4)°	Block, colorless
V = 791.3 (3) Å³	0.23 × 0.21 × 0.19 mm
Z = 4

Data collection top

Bruker SMART APEX CCD diffractometer	1568 independent reflections
Radiation source: fine-focus sealed tube	1151 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.093
ω scans	θ_max = 26.1°, θ_min = 2.4°
Absorption correction: numerical (SADABS; Sheldrick, 2003)	h = −10→10
T_min = 0.118, T_max = 0.429	k = −9→9
8611 measured reflections	l = −14→14

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Primary atom site location: structure-invariant direct methods
R[F² > 2σ(F²)] = 0.037	Secondary atom site location: difference Fourier map
wR(F²) = 0.091	w = 1/[σ²(F_o²) + (0.0376P)²] where P = (F_o² + 2F_c²)/3
S = 1.05	(Δ/σ)_max < 0.001
1568 reflections	Δρ_max = 1.28 e Å⁻³
118 parameters	Δρ_min = −0.90 e Å⁻³

Crystal data top

Rb₂Ga₂O(BO₃)₂	V = 791.3 (3) Å³
M_r = 444.00	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 8.8115 (18) Å	µ = 19.03 mm⁻¹
b = 7.7224 (16) Å	T = 297 K
c = 11.997 (3) Å	0.23 × 0.21 × 0.19 mm
β = 104.246 (4)°

Data collection top

Bruker SMART APEX CCD diffractometer	1568 independent reflections
Absorption correction: numerical (SADABS; Sheldrick, 2003)	1151 reflections with I > 2σ(I)
T_min = 0.118, T_max = 0.429	R_int = 0.093
8611 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.037	118 parameters
wR(F²) = 0.091	0 restraints
S = 1.05	Δρ_max = 1.28 e Å⁻³
1568 reflections	Δρ_min = −0.90 e Å⁻³

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
Rb1	0.05407 (9)	0.12523 (11)	0.15061 (7)	0.0276 (2)
Rb2	0.53288 (9)	0.12728 (10)	0.62677 (7)	0.0265 (2)
Ga1	0.84630 (9)	0.12201 (10)	0.38547 (7)	0.0183 (2)
Ga2	0.31410 (9)	0.06933 (11)	0.86673 (8)	0.0191 (2)
B1	0.6554 (10)	0.0915 (10)	0.9123 (8)	0.0166 (19)
B2	0.1834 (10)	0.1269 (11)	0.4388 (8)	0.0181 (18)
O1	0.5159 (5)	0.0083 (6)	0.8667 (5)	0.0221 (13)
O2	0.7394 (6)	0.0677 (7)	0.0235 (4)	0.0249 (13)
O3	0.7155 (6)	0.1924 (7)	0.8410 (5)	0.0261 (13)
O4	0.0442 (5)	0.2139 (6)	0.4178 (5)	0.0247 (13)
O5	0.3091 (5)	0.2014 (6)	0.4049 (5)	0.0215 (12)
O6	0.7902 (6)	0.0280 (7)	0.5097 (5)	0.0286 (14)
O7	0.1781 (6)	0.0322 (7)	0.7290 (5)	0.0248 (12)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Rb1	0.0180 (4)	0.0338 (5)	0.0310 (5)	−0.0050 (3)	0.0063 (4)	−0.0004 (4)
Rb2	0.0225 (4)	0.0282 (4)	0.0260 (5)	0.0032 (3)	0.0008 (3)	−0.0024 (4)
Ga1	0.0125 (4)	0.0193 (4)	0.0237 (5)	0.0007 (3)	0.0055 (4)	0.0004 (4)
Ga2	0.0122 (4)	0.0203 (4)	0.0252 (5)	−0.0007 (3)	0.0052 (4)	0.0005 (4)
B1	0.017 (4)	0.011 (4)	0.026 (5)	0.003 (3)	0.014 (4)	0.000 (4)
B2	0.015 (4)	0.017 (4)	0.022 (5)	0.000 (3)	0.005 (4)	0.002 (4)
O1	0.008 (3)	0.022 (3)	0.037 (4)	−0.001 (2)	0.007 (2)	−0.005 (2)
O2	0.016 (3)	0.031 (3)	0.025 (3)	−0.008 (2)	0.002 (2)	0.010 (3)
O3	0.024 (3)	0.024 (3)	0.029 (3)	−0.012 (2)	0.004 (3)	0.000 (3)
O4	0.008 (3)	0.023 (3)	0.043 (4)	−0.006 (2)	0.008 (2)	0.001 (3)
O5	0.011 (3)	0.021 (3)	0.035 (3)	0.001 (2)	0.011 (2)	0.004 (2)
O6	0.029 (3)	0.024 (3)	0.040 (4)	0.004 (2)	0.023 (3)	0.010 (3)
O7	0.019 (3)	0.026 (3)	0.026 (3)	0.003 (2)	−0.001 (2)	−0.006 (3)

Geometric parameters (Å, º) top

Rb1—O2ⁱ	2.851 (5)	Ga2—O2^iv	1.838 (5)
Rb1—O7ⁱⁱ	2.928 (5)	Ga2—O5^viii	1.832 (5)
Rb1—O7ⁱⁱⁱ	3.034 (5)	Ga2—O7	1.810 (5)
Rb1—O4ⁱⁱ	3.039 (5)	Ga2—Rb1ⁱⁱⁱ	3.5346 (12)
Rb1—O3^iv	3.170 (5)	Ga2—Rb2^xiii	3.6641 (13)
Rb1—B1^iv	3.298 (8)	Ga2—Rb1^viii	3.8226 (12)
Rb1—O4	3.300 (6)	Ga2—Rb2^viii	3.9973 (13)
Rb1—O4^v	3.341 (5)	B1—O1	1.376 (10)
Rb1—B2	3.363 (9)	B1—O2^xiv	1.370 (10)
Rb1—O5	3.365 (5)	B1—O3	1.358 (10)
Rb1—O2^vi	3.430 (6)	B1—Rb1^iv	3.298 (8)
Rb1—Ga2ⁱⁱⁱ	3.5346 (12)	B1—Rb2^viii	3.724 (8)
Rb2—O3	2.722 (5)	B2—O4	1.366 (9)
Rb2—O5	2.953 (5)	B2—O5	1.395 (9)
Rb2—O5^iv	2.964 (5)	B2—O6^iv	1.341 (10)
Rb2—O1^vii	2.977 (5)	B2—Rb2^iv	3.419 (8)
Rb2—O6	3.045 (5)	B2—Rb1^viii	3.584 (9)
Rb2—O1	3.060 (5)	O1—Rb2^xiii	2.977 (5)
Rb2—O6^iv	3.151 (6)	O2—B1^xv	1.370 (10)
Rb2—B2	3.340 (9)	O2—Ga2^iv	1.838 (5)
Rb2—B1	3.340 (9)	O2—Rb1^ix	2.851 (5)
Rb2—O2^viii	3.392 (6)	O2—Rb2ⁱⁱ	3.392 (6)
Rb2—B2^iv	3.419 (8)	O2—Rb1^vi	3.430 (6)
Rb2—Rb2^iv	3.5477 (17)	O3—Ga1^viii	1.834 (5)
Ga1—O3ⁱⁱ	1.834 (5)	O3—Rb1^iv	3.170 (5)
Ga1—O4^ix	1.834 (5)	O4—Ga1ⁱ	1.834 (5)
Ga1—O6	1.831 (5)	O4—Rb1^viii	3.039 (5)
Ga1—O7^iv	1.790 (5)	O4—Rb1^xvi	3.341 (5)
Ga1—Rb1^ix	3.7189 (13)	O5—Ga2ⁱⁱ	1.832 (5)
Ga1—Rb1^x	3.7966 (13)	O5—Rb2^iv	2.964 (5)
Ga1—Rb2^iv	3.8275 (13)	O6—B2^iv	1.341 (10)
Ga1—Rb1^xi	3.9828 (14)	O6—Rb2^iv	3.151 (6)
Ga1—Rb1^xii	4.0307 (14)	O7—Ga1^iv	1.790 (5)
Ga1—Rb2ⁱⁱ	4.0975 (12)	O7—Rb1^viii	2.928 (5)
Ga2—O1	1.840 (5)	O7—Rb1ⁱⁱⁱ	3.034 (5)

O2ⁱ—Rb1—O7ⁱⁱ	123.34 (15)	Rb1^x—Ga1—Rb2^iv	121.81 (3)
O2ⁱ—Rb1—O7ⁱⁱⁱ	60.74 (14)	O7^iv—Ga1—Rb1^xi	42.60 (17)
O7ⁱⁱ—Rb1—O7ⁱⁱⁱ	116.83 (11)	O6—Ga1—Rb1^xi	79.48 (16)
O2ⁱ—Rb1—O4ⁱⁱ	76.60 (14)	O4^ix—Ga1—Rb1^xi	99.91 (16)
O7ⁱⁱ—Rb1—O4ⁱⁱ	81.35 (14)	O3ⁱⁱ—Ga1—Rb1^xi	149.37 (17)
O7ⁱⁱⁱ—Rb1—O4ⁱⁱ	137.01 (13)	Rb1^ix—Ga1—Rb1^xi	76.19 (2)
O2ⁱ—Rb1—O3^iv	115.30 (15)	Rb1^x—Ga1—Rb1^xi	120.83 (2)
O7ⁱⁱ—Rb1—O3^iv	120.23 (13)	Rb2^iv—Ga1—Rb1^xi	74.04 (2)
O7ⁱⁱⁱ—Rb1—O3^iv	100.16 (13)	O7^iv—Ga1—Rb1^xii	123.18 (18)
O4ⁱⁱ—Rb1—O3^iv	102.65 (13)	O6—Ga1—Rb1^xii	125.38 (17)
O2ⁱ—Rb1—B1^iv	120.40 (19)	O4^ix—Ga1—Rb1^xii	55.16 (16)
O7ⁱⁱ—Rb1—B1^iv	106.42 (17)	O3ⁱⁱ—Ga1—Rb1^xii	49.70 (17)
O7ⁱⁱⁱ—Rb1—B1^iv	123.92 (17)	Rb1^ix—Ga1—Rb1^xii	75.60 (2)
O4ⁱⁱ—Rb1—B1^iv	81.11 (18)	Rb1^x—Ga1—Rb1^xii	61.41 (3)
O3^iv—Rb1—B1^iv	24.13 (17)	Rb2^iv—Ga1—Rb1^xii	133.78 (3)
O2ⁱ—Rb1—O4	107.29 (14)	Rb1^xi—Ga1—Rb1^xii	149.02 (3)
O7ⁱⁱ—Rb1—O4	66.27 (13)	O7^iv—Ga1—Rb2ⁱⁱ	78.58 (17)
O7ⁱⁱⁱ—Rb1—O4	55.84 (13)	O6—Ga1—Rb2ⁱⁱ	122.49 (17)
O4ⁱⁱ—Rb1—O4	143.75 (4)	O4^ix—Ga1—Rb2ⁱⁱ	113.96 (17)
O3^iv—Rb1—O4	107.42 (13)	O3ⁱⁱ—Ga1—Rb2ⁱⁱ	32.03 (17)
B1^iv—Rb1—O4	122.35 (19)	Rb1^ix—Ga1—Rb2ⁱⁱ	77.80 (3)
O2ⁱ—Rb1—O4^v	63.98 (14)	Rb1^x—Ga1—Rb2ⁱⁱ	119.20 (3)
O7ⁱⁱ—Rb1—O4^v	172.59 (13)	Rb2^iv—Ga1—Rb2ⁱⁱ	77.84 (2)
O7ⁱⁱⁱ—Rb1—O4^v	64.64 (13)	Rb1^xi—Ga1—Rb2ⁱⁱ	119.89 (3)
O4ⁱⁱ—Rb1—O4^v	102.47 (12)	Rb1^xii—Ga1—Rb2ⁱⁱ	65.61 (2)
O3^iv—Rb1—O4^v	52.94 (12)	O7—Ga2—O5^viii	109.3 (2)
B1^iv—Rb1—O4^v	68.29 (16)	O7—Ga2—O2^iv	109.5 (2)
O4—Rb1—O4^v	111.63 (12)	O5^viii—Ga2—O2^iv	110.6 (2)
O2ⁱ—Rb1—B2	126.09 (18)	O7—Ga2—O1	112.5 (2)
O7ⁱⁱ—Rb1—B2	70.20 (18)	O5^viii—Ga2—O1	109.3 (2)
O7ⁱⁱⁱ—Rb1—B2	67.02 (17)	O2^iv—Ga2—O1	105.7 (2)
O4ⁱⁱ—Rb1—B2	150.35 (17)	O7—Ga2—Rb1ⁱⁱⁱ	59.13 (17)
O3^iv—Rb1—B2	85.29 (17)	O5^viii—Ga2—Rb1ⁱⁱⁱ	110.32 (14)
B1^iv—Rb1—B2	98.7 (2)	O2^iv—Ga2—Rb1ⁱⁱⁱ	53.43 (16)
O4—Rb1—B2	23.63 (16)	O1—Ga2—Rb1ⁱⁱⁱ	139.84 (15)
O4^v—Rb1—B2	104.94 (17)	O7—Ga2—Rb2^xiii	91.67 (16)
O2ⁱ—Rb1—O5	148.92 (14)	O5^viii—Ga2—Rb2^xiii	157.90 (16)
O7ⁱⁱ—Rb1—O5	55.79 (13)	O2^iv—Ga2—Rb2^xiii	66.83 (17)
O7ⁱⁱⁱ—Rb1—O5	90.94 (13)	O1—Ga2—Rb2^xiii	53.89 (15)
O4ⁱⁱ—Rb1—O5	128.56 (13)	Rb1ⁱⁱⁱ—Ga2—Rb2^xiii	86.15 (3)
O3^iv—Rb1—O5	80.03 (13)	O7—Ga2—Rb1^viii	47.68 (16)
B1^iv—Rb1—O5	85.03 (18)	O5^viii—Ga2—Rb1^viii	61.69 (16)
O4—Rb1—O5	41.80 (11)	O2^iv—Ga2—Rb1^viii	128.63 (16)
O4^v—Rb1—O5	117.62 (12)	O1—Ga2—Rb1^viii	125.18 (17)
B2—Rb1—O5	23.93 (16)	Rb1ⁱⁱⁱ—Ga2—Rb1^viii	80.45 (2)
O2ⁱ—Rb1—O2^vi	101.45 (12)	Rb2^xiii—Ga2—Rb1^viii	138.19 (3)
O7ⁱⁱ—Rb1—O2^vi	112.08 (14)	O7—Ga2—Rb2	71.19 (17)
O7ⁱⁱⁱ—Rb1—O2^vi	129.57 (13)	O5^viii—Ga2—Rb2	96.97 (15)
O4ⁱⁱ—Rb1—O2^vi	61.13 (12)	O2^iv—Ga2—Rb2	149.64 (18)
O3^iv—Rb1—O2^vi	41.56 (13)	O1—Ga2—Rb2	50.97 (17)
B1^iv—Rb1—O2^vi	23.39 (18)	Rb1ⁱⁱⁱ—Ga2—Rb2	128.63 (3)
O4—Rb1—O2^vi	145.74 (12)	Rb2^xiii—Ga2—Rb2	82.84 (2)
O4^v—Rb1—O2^vi	65.28 (12)	Rb1^viii—Ga2—Rb2	75.46 (3)
B2—Rb1—O2^vi	122.11 (17)	O7—Ga2—Rb2^viii	152.81 (16)
O5—Rb1—O2^vi	106.98 (12)	O5^viii—Ga2—Rb2^viii	43.56 (16)
O2ⁱ—Rb1—Ga2ⁱⁱⁱ	31.19 (10)	O2^iv—Ga2—Rb2^viii	86.43 (17)
O7ⁱⁱ—Rb1—Ga2ⁱⁱⁱ	131.89 (11)	O1—Ga2—Rb2^viii	82.52 (16)
O7ⁱⁱⁱ—Rb1—Ga2ⁱⁱⁱ	30.80 (10)	Rb1ⁱⁱⁱ—Ga2—Rb2^viii	123.67 (3)
O4ⁱⁱ—Rb1—Ga2ⁱⁱⁱ	107.55 (9)	Rb2^xiii—Ga2—Rb2^viii	115.16 (3)
O3^iv—Rb1—Ga2ⁱⁱⁱ	104.14 (9)	Rb1^viii—Ga2—Rb2^viii	105.14 (3)
B1^iv—Rb1—Ga2ⁱⁱⁱ	121.58 (14)	Rb2—Ga2—Rb2^viii	106.28 (3)
O4—Rb1—Ga2ⁱⁱⁱ	84.39 (8)	O3—B1—O2^xiv	119.4 (7)
O4^v—Rb1—Ga2ⁱⁱⁱ	53.33 (8)	O3—B1—O1	117.8 (8)
B2—Rb1—Ga2ⁱⁱⁱ	97.81 (14)	O2^xiv—B1—O1	122.7 (7)
O5—Rb1—Ga2ⁱⁱⁱ	121.74 (8)	O3—B1—Rb1^iv	72.7 (4)
O2^vi—Rb1—Ga2ⁱⁱⁱ	113.35 (9)	O2^xiv—B1—Rb1^iv	83.7 (4)
O3—Rb2—O5	157.47 (16)	O1—B1—Rb1^iv	109.9 (4)
O3—Rb2—O5^iv	95.27 (15)	O3—B1—Rb2	52.0 (4)
O5—Rb2—O5^iv	106.33 (12)	O2^xiv—B1—Rb2	166.2 (5)
O3—Rb2—O1^vii	81.27 (15)	O1—B1—Rb2	66.4 (4)
O5—Rb2—O1^vii	76.31 (14)	Rb1^iv—B1—Rb2	83.14 (19)
O5^iv—Rb2—O1^vii	157.67 (13)	O3—B1—Rb2^viii	109.0 (5)
O3—Rb2—O6	98.49 (16)	O2^xiv—B1—Rb2^viii	65.4 (4)
O5—Rb2—O6	92.34 (14)	O1—B1—Rb2^viii	99.5 (4)
O5^iv—Rb2—O6	45.46 (13)	Rb1^iv—B1—Rb2^viii	145.8 (3)
O1^vii—Rb2—O6	112.93 (14)	Rb2—B1—Rb2^viii	125.8 (2)
O3—Rb2—O1	47.31 (13)	O6^iv—B2—O4	124.7 (7)
O5—Rb2—O1	136.88 (12)	O6^iv—B2—O5	116.3 (7)
O5^iv—Rb2—O1	89.80 (13)	O4—B2—O5	119.0 (7)
O1^vii—Rb2—O1	103.37 (11)	O6^iv—B2—Rb2	70.3 (4)
O6—Rb2—O1	124.94 (13)	O4—B2—Rb2	139.5 (5)
O3—Rb2—O6^iv	144.03 (14)	O5—B2—Rb2	62.0 (4)
O5—Rb2—O6^iv	44.59 (13)	O6^iv—B2—Rb1	116.6 (5)
O5^iv—Rb2—O6^iv	90.03 (13)	O4—B2—Rb1	75.6 (4)
O1^vii—Rb2—O6^iv	105.77 (13)	O5—B2—Rb1	78.1 (4)
O6—Rb2—O6^iv	110.17 (11)	Rb2—B2—Rb1	135.8 (3)
O1—Rb2—O6^iv	97.31 (13)	O6^iv—B2—Rb2^iv	62.6 (4)
O3—Rb2—B2	150.50 (19)	O4—B2—Rb2^iv	156.1 (6)
O5—Rb2—B2	24.64 (17)	O5—B2—Rb2^iv	59.4 (4)
O5^iv—Rb2—B2	107.28 (18)	Rb2—B2—Rb2^iv	63.31 (15)
O1^vii—Rb2—B2	84.46 (17)	Rb1—B2—Rb2^iv	80.99 (19)
O6—Rb2—B2	110.85 (19)	O6^iv—B2—Rb1^viii	101.5 (5)
O1—Rb2—B2	112.62 (17)	O4—B2—Rb1^viii	56.0 (4)
O6^iv—Rb2—B2	23.61 (16)	O5—B2—Rb1^viii	113.6 (5)
O3—Rb2—B1	23.13 (17)	Rb2—B2—Rb1^viii	85.5 (2)
O5—Rb2—B1	156.39 (16)	Rb1—B2—Rb1^viii	130.1 (2)
O5^iv—Rb2—B1	90.97 (16)	Rb2^iv—B2—Rb1^viii	148.0 (3)
O1^vii—Rb2—B1	93.85 (17)	B1—O1—Ga2	130.5 (5)
O6—Rb2—B1	111.28 (17)	B1—O1—Rb2^xiii	124.9 (4)
O1—Rb2—B1	24.32 (16)	Ga2—O1—Rb2^xiii	96.17 (18)
O6^iv—Rb2—B1	121.60 (17)	B1—O1—Rb2	89.3 (4)
B2—Rb2—B1	134.8 (2)	Ga2—O1—Rb2	101.2 (2)
O3—Rb2—O2^viii	88.32 (14)	Rb2^xiii—O1—Rb2	111.24 (16)
O5—Rb2—O2^viii	80.53 (13)	B1^xv—O2—Ga2^iv	127.1 (5)
O5^iv—Rb2—O2^viii	103.70 (12)	B1^xv—O2—Rb1^ix	136.1 (4)
O1^vii—Rb2—O2^viii	54.35 (12)	Ga2^iv—O2—Rb1^ix	95.4 (2)
O6—Rb2—O2^viii	58.60 (12)	B1^xv—O2—Rb2ⁱⁱ	93.0 (4)
O1—Rb2—O2^viii	134.98 (13)	Ga2^iv—O2—Rb2ⁱⁱ	83.28 (19)
O6^iv—Rb2—O2^viii	124.89 (13)	Rb1^ix—O2—Rb2ⁱⁱ	103.59 (16)
B2—Rb2—O2^viii	104.03 (17)	B1^xv—O2—Rb1^vi	72.9 (4)
B1—Rb2—O2^viii	111.40 (16)	Ga2^iv—O2—Rb1^vi	117.0 (2)
O3—Rb2—B2^iv	91.56 (19)	Rb1^ix—O2—Rb1^vi	78.55 (12)
O5—Rb2—B2^iv	105.54 (18)	Rb2ⁱⁱ—O2—Rb1^vi	159.51 (17)
O5^iv—Rb2—B2^iv	23.90 (16)	B1—O3—Ga1^viii	125.4 (5)
O1^vii—Rb2—B2^iv	133.78 (17)	B1—O3—Rb2	104.9 (5)
O6—Rb2—B2^iv	23.01 (17)	Ga1^viii—O3—Rb2	127.0 (2)
O1—Rb2—B2^iv	104.57 (17)	B1—O3—Rb1^iv	83.2 (4)
O6^iv—Rb2—B2^iv	106.29 (17)	Ga1^viii—O3—Rb1^iv	104.1 (2)
B2—Rb2—B2^iv	116.69 (15)	Rb2—O3—Rb1^iv	96.45 (16)
B1—Rb2—B2^iv	96.8 (2)	B2—O4—Ga1ⁱ	127.8 (5)
O2^viii—Rb2—B2^iv	80.00 (16)	B2—O4—Rb1^viii	102.1 (5)
O3—Rb2—Rb2^iv	147.74 (12)	Ga1ⁱ—O4—Rb1^viii	99.4 (2)
O5—Rb2—Rb2^iv	53.31 (10)	B2—O4—Rb1	80.8 (4)
O5^iv—Rb2—Rb2^iv	53.02 (10)	Ga1ⁱ—O4—Rb1	88.01 (19)
O1^vii—Rb2—Rb2^iv	125.17 (11)	Rb1^viii—O4—Rb1	167.46 (17)
O6—Rb2—Rb2^iv	56.49 (11)	B2—O4—Rb1^xvi	132.8 (4)
O1—Rb2—Rb2^iv	127.20 (10)	Ga1ⁱ—O4—Rb1^xvi	98.07 (19)
O6^iv—Rb2—Rb2^iv	53.68 (10)	Rb1^viii—O4—Rb1^xvi	77.53 (12)
B2—Rb2—Rb2^iv	59.44 (15)	Rb1—O4—Rb1^xvi	91.48 (13)
B1—Rb2—Rb2^iv	140.98 (13)	B2—O5—Ga2ⁱⁱ	122.8 (5)
O2^viii—Rb2—Rb2^iv	93.49 (9)	B2—O5—Rb2	93.4 (4)
B2^iv—Rb2—Rb2^iv	57.25 (15)	Ga2ⁱⁱ—O5—Rb2	111.1 (2)
O7^iv—Ga1—O6	110.8 (2)	B2—O5—Rb2^iv	96.7 (4)
O7^iv—Ga1—O4^ix	110.4 (2)	Ga2ⁱⁱ—O5—Rb2^iv	139.0 (2)
O6—Ga1—O4^ix	114.5 (2)	Rb2—O5—Rb2^iv	73.67 (11)
O7^iv—Ga1—O3ⁱⁱ	110.4 (2)	B2—O5—Rb1	77.9 (4)
O6—Ga1—O3ⁱⁱ	105.7 (2)	Ga2ⁱⁱ—O5—Rb1	89.68 (19)
O4^ix—Ga1—O3ⁱⁱ	104.8 (2)	Rb2—O5—Rb1	158.76 (17)
O7^iv—Ga1—Rb1^ix	53.98 (17)	Rb2^iv—O5—Rb1	87.95 (13)
O6—Ga1—Rb1^ix	154.26 (16)	B2^iv—O6—Ga1	132.7 (5)
O4^ix—Ga1—Rb1^ix	62.46 (17)	B2^iv—O6—Rb2	94.4 (4)
O3ⁱⁱ—Ga1—Rb1^ix	99.52 (17)	Ga1—O6—Rb2	131.0 (2)
O7^iv—Ga1—Rb1^x	157.95 (16)	B2^iv—O6—Rb2^iv	86.1 (4)
O6—Ga1—Rb1^x	72.13 (18)	Ga1—O6—Rb2^iv	96.8 (2)
O4^ix—Ga1—Rb1^x	52.16 (17)	Rb2—O6—Rb2^iv	69.83 (11)
O3ⁱⁱ—Ga1—Rb1^x	88.92 (17)	Ga1^iv—O7—Ga2	137.2 (3)
Rb1^ix—Ga1—Rb1^x	113.93 (3)	Ga1^iv—O7—Rb1^viii	113.0 (2)
O7^iv—Ga1—Rb2^iv	72.36 (17)	Ga2—O7—Rb1^viii	105.1 (2)
O6—Ga1—Rb2^iv	54.84 (18)	Ga1^iv—O7—Rb1ⁱⁱⁱ	97.5 (2)
O4^ix—Ga1—Rb2^iv	168.11 (17)	Ga2—O7—Rb1ⁱⁱⁱ	90.1 (2)
O3ⁱⁱ—Ga1—Rb2^iv	84.37 (17)	Rb1^viii—O7—Rb1ⁱⁱⁱ	105.83 (16)
Rb1^ix—Ga1—Rb2^iv	124.20 (3)

Symmetry codes: (i) x−1, y, z; (ii) x, −y+1/2, z−1/2; (iii) −x, −y, −z+1; (iv) −x+1, −y, −z+1; (v) −x, y−1/2, −z+1/2; (vi) −x+1, −y, −z; (vii) −x+1, y+1/2, −z+3/2; (viii) x, −y+1/2, z+1/2; (ix) x+1, y, z; (x) x+1, −y+1/2, z+1/2; (xi) −x+1, y−1/2, −z+1/2; (xii) −x+1, y+1/2, −z+1/2; (xiii) −x+1, y−1/2, −z+3/2; (xiv) x, y, z+1; (xv) x, y, z−1; (xvi) −x, y+1/2, −z+1/2.

Experimental details

Crystal data
Chemical formula	Rb₂Ga₂O(BO₃)₂
M_r	444.00
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	297
a, b, c (Å)	8.8115 (18), 7.7224 (16), 11.997 (3)
β (°)	104.246 (4)
V (Å³)	791.3 (3)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	19.03
Crystal size (mm)	0.23 × 0.21 × 0.19

Data collection
Diffractometer	Bruker SMART APEX CCD diffractometer
Absorption correction	Numerical (SADABS; Sheldrick, 2003)
T_min, T_max	0.118, 0.429
No. of measured, independent and observed [I > 2σ(I)] reflections	8611, 1568, 1151
R_int	0.093
(sin θ/λ)_max (Å⁻¹)	0.619

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.091, 1.05
No. of reflections	1568
No. of parameters	118
Δρ_max, Δρ_min (e Å⁻³)	1.28, −0.90

Computer programs: SMART (Bruker, 2005), SAINT-Plus (Bruker, 2003), SHELXTL (Sheldrick, 2008), DIAMOND (Brandenburg & Putz, 2007).

Selected geometric parameters (Å, º) top

Ga1—O3ⁱ	1.834 (5)	Ga2—O7	1.810 (5)
Ga1—O4ⁱⁱ	1.834 (5)	B1—O1	1.376 (10)
Ga1—O6	1.831 (5)	B1—O2^v	1.370 (10)
Ga1—O7ⁱⁱⁱ	1.790 (5)	B1—O3	1.358 (10)
Ga2—O1	1.840 (5)	B2—O4	1.366 (9)
Ga2—O2ⁱⁱⁱ	1.838 (5)	B2—O5	1.395 (9)
Ga2—O5^iv	1.832 (5)	B2—O6ⁱⁱⁱ	1.341 (10)

O7ⁱⁱⁱ—Ga1—O6	110.8 (2)	O7—Ga2—O1	112.5 (2)
O7ⁱⁱⁱ—Ga1—O4ⁱⁱ	110.4 (2)	O5^iv—Ga2—O1	109.3 (2)
O6—Ga1—O4ⁱⁱ	114.5 (2)	O2ⁱⁱⁱ—Ga2—O1	105.7 (2)
O7ⁱⁱⁱ—Ga1—O3ⁱ	110.4 (2)	O3—B1—O2^v	119.4 (7)
O6—Ga1—O3ⁱ	105.7 (2)	O3—B1—O1	117.8 (8)
O4ⁱⁱ—Ga1—O3ⁱ	104.8 (2)	O2^v—B1—O1	122.7 (7)
O7—Ga2—O5^iv	109.3 (2)	O6ⁱⁱⁱ—B2—O4	124.7 (7)
O7—Ga2—O2ⁱⁱⁱ	109.5 (2)	O6ⁱⁱⁱ—B2—O5	116.3 (7)
O5^iv—Ga2—O2ⁱⁱⁱ	110.6 (2)	O4—B2—O5	119.0 (7)

Symmetry codes: (i) x, −y+1/2, z−1/2; (ii) x+1, y, z; (iii) −x+1, −y, −z+1; (iv) x, −y+1/2, z+1/2; (v) x, y, z+1.

Acknowledgements

This work was supported by the Nebraska Research Initiative.

References

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