The langbeinite type Rb₂TiY(PO₄)₃

Dirubidium titanium yttrium triphosphate belongs to the langbeinite structure type with a framework of MO₆ octa­hedra (M = Ti, Y) sharing corners with PO₄ tetra­hedra and vice versa, creating cages in which the Rb⁺ cations are located. The compound exhibits mixed Ti/Y populations in the two crystallographically independent octa­hedral sites of symmetry 3. More than two-thirds of the yttrium is found in one site and the remaining amount in the other; this is caused by the difference in coordination for the two sites.

Key indicators

• Single-crystal X-ray study
• T = 296 K
• Mean [sigma](P-O) = 0.005 Å
• Disorder in main residue
• R factor = 0.033
• wR factor = 0.079
• Data-to-parameter ratio = 20.9

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT112_ALERT_2_B ADDSYM Detects Additional (Pseudo) Symm. Elem...         -4
PLAT112_ALERT_2_B ADDSYM Detects Additional (Pseudo) Symm. Elem...         -4
PLAT112_ALERT_2_B ADDSYM Detects Additional (Pseudo) Symm. Elem...         -4

Alert level C
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for         O2
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for         O3
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for          P
PLAT301_ALERT_3_C Main Residue  Disorder .........................      11.00 Perc.

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           31.89
           From the CIF: _reflns_number_total               1254
           Count of symmetry unique reflns          709
           Completeness (_total/calc)            176.87%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured       545
           Fraction of Friedel pairs measured     0.769
           Are heavy atom types Z>Si present        yes

   0 ALERT level A = In general: serious problem
   3 ALERT level B = Potentially serious problem
   4 ALERT level C = Check and explain
   1 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   6 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997), DIAMOND (Brandenburg, 2004) and POV-RAY (Persistence of Vision Raytracer Pty. Ltd., 2004); software used to prepare material for publication: WinGX (Farrugia, 1999).

Dirubidium titanium yttrium tris(phosphate)

Crystal data

Rb2TiY(PO4)3	Dx = 3.637 Mg m^−3
Mr = 592.66	Mo Kα radiation, λ = 0.71073 Å
Cubic, P213	Cell parameters from 14 reflections
Hall symbol: P 2ac 2ab 3	θ = 25.0–31.6°
a = 10.2674 (4) Å	µ = 15.51 mm^−1
V = 1082.38 (7) Å^3	T = 296 K
Z = 4	Tetrahedron, colourless
F(000) = 1104	0.25 × 0.25 × 0.25 mm

Data collection

Enraf–Nonius CAD-4 diffractometer	Rint = 0.062
ω–2θ scans	θmax = 31.9°, θmin = 3.4°
Absorption correction: analytical (Alcock, 1970)	h = 0→15
Tmin = 0.837, Tmax = 0.867	k = 0→15
4075 measured reflections	l = −15→15
1254 independent reflections	2 standard reflections every 120 min
1091 reflections with I > 2σ(I)	intensity decay: none

Refinement

Refinement on F^2	8 constraints
Least-squares matrix: full	w = 1/[σ^2(Fo^2) + (0.04P)^2 + 1.5P] where P = (Fo^2 + 2Fc^2)/3
R[F^2 > 2σ(F^2)] = 0.033	(Δ/σ)max < 0.001
wR(F^2) = 0.079	Δρmax = 0.61 e Å^−3
S = 1.06	Δρmin = −0.83 e Å^−3
1254 reflections	Absolute structure: Flack (1983), 539 Friedel pairs
60 parameters	Absolute structure parameter: −0.012 (14)
1 restraint

Special details

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. Constraints used during the refinement:

Equal Atomic Displacements parameters Ti1 Y1 Equal Atomic Displacements parameters Ti2 Y2 Equal Atomic coordinates Ti1 Y1 Equal Atomic coordinates Ti2 Y2 Occupancy of Ti1+Y1 = 1.0 Occupancy of Ti2+Y2 = 1.0

Restraints used: Occupancy Ti1 + Ti2 = 1.0

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq	Occ. (<1)
Rb1	0.42927 (5)	0.57073 (5)	1.07073 (5)	0.02301 (18)
Rb2	0.20746 (5)	0.79254 (5)	1.29254 (5)	0.0270 (2)
Y1	0.08281 (4)	0.58281 (4)	0.91719 (4)	0.00932 (16)	0.702 (3)
Ti1	0.08281 (4)	0.58281 (4)	0.91719 (4)	0.00932 (16)	0.298 (3)
Y2	0.35274 (6)	0.85274 (6)	0.64726 (6)	0.0123 (2)	0.298 (3)
Ti2	0.35274 (6)	0.85274 (6)	0.64726 (6)	0.0123 (2)	0.702 (3)
P	0.26279 (13)	0.87945 (12)	0.95905 (13)	0.0196 (2)
O1	0.3988 (4)	0.8521 (5)	1.0071 (4)	0.0362 (10)
O2	0.1782 (5)	0.7599 (4)	0.9800 (5)	0.0429 (12)
O3	0.2651 (5)	0.9170 (5)	0.8143 (5)	0.0398 (11)
O4	0.2026 (5)	0.9918 (5)	1.0372 (6)	0.0535 (15)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Rb1	0.02301 (18)	0.02301 (18)	0.02301 (18)	0.00196 (17)	0.00196 (17)	−0.00196 (17)
Rb2	0.0270 (2)	0.0270 (2)	0.0270 (2)	0.00101 (19)	0.00101 (19)	−0.00101 (19)
Y1	0.00932 (16)	0.00932 (16)	0.00932 (16)	−0.00091 (15)	0.00091 (15)	0.00091 (15)
Ti1	0.00932 (16)	0.00932 (16)	0.00932 (16)	−0.00091 (15)	0.00091 (15)	0.00091 (15)
Y2	0.0123 (2)	0.0123 (2)	0.0123 (2)	0.0003 (2)	−0.0003 (2)	−0.0003 (2)
Ti2	0.0123 (2)	0.0123 (2)	0.0123 (2)	0.0003 (2)	−0.0003 (2)	−0.0003 (2)
P	0.0214 (6)	0.0154 (5)	0.0219 (6)	−0.0014 (4)	−0.0016 (4)	−0.0029 (4)
O1	0.033 (2)	0.039 (2)	0.036 (2)	0.0069 (18)	−0.0112 (17)	0.0032 (19)
O2	0.051 (3)	0.033 (2)	0.044 (3)	−0.022 (2)	0.008 (2)	−0.004 (2)
O3	0.048 (3)	0.037 (2)	0.034 (2)	−0.003 (2)	−0.0113 (19)	0.0151 (18)
O4	0.042 (3)	0.035 (3)	0.083 (4)	0.007 (2)	−0.005 (3)	−0.035 (3)

Geometric parameters (Å, º)

Rb1—O1^i	2.978 (5)	Y1—Rb1^xii	3.8929 (4)
Rb1—O1^ii	2.978 (5)	Y1—Rb1^x	3.8929 (4)
Rb1—O1	2.978 (5)	Y1—Rb2^x	4.5964 (6)
Rb1—O4^iii	3.084 (5)	Y1—Rb2^xii	4.5964 (6)
Rb1—O4^iv	3.084 (5)	Y2—O4^xiii	2.036 (4)
Rb1—O4^v	3.084 (5)	Y2—O4^xiv	2.036 (4)
Rb1—O2^iii	3.135 (5)	Y2—O4^xv	2.036 (4)
Rb1—O2^v	3.135 (5)	Y2—O3^xi	2.046 (5)
Rb1—O2^iv	3.135 (5)	Y2—O3	2.046 (5)
Rb1—O2^i	3.359 (5)	Y2—O3^iii	2.046 (5)
Rb1—O2^ii	3.359 (5)	Y2—P^xi	3.3432 (15)
Rb1—O2	3.359 (5)	Y2—P^iii	3.3432 (15)
Rb2—O3^vi	3.004 (5)	Y2—P	3.3432 (15)
Rb2—O3^vii	3.004 (5)	Y2—Rb1^xvi	3.8768 (13)
Rb2—O3^viii	3.004 (5)	Y2—Rb2^xvii	3.9839 (5)
Rb2—O2^i	3.240 (5)	Y2—Rb2^xiv	3.9839 (5)
Rb2—O2^ii	3.240 (5)	P—O1	1.508 (4)
Rb2—O2	3.240 (5)	P—O2	1.520 (4)
Rb2—O4^i	3.326 (7)	P—O4	1.535 (5)
Rb2—O4	3.326 (7)	P—O3	1.535 (5)
Rb2—O4^ii	3.326 (7)	P—Rb1^x	3.4758 (14)
Rb2—O4^vi	3.473 (7)	P—Rb2^xiv	3.7893 (15)
Rb2—O4^viii	3.473 (7)	O1—Ti1^v	2.149 (4)
Rb2—O4^vii	3.473 (7)	O1—Y1^v	2.149 (4)
Y1—O1^ix	2.149 (4)	O2—Rb1^x	3.135 (5)
Y1—O1^ii	2.149 (4)	O3—Rb2^xiv	3.004 (5)
Y1—O1^x	2.149 (4)	O4—Ti2^vi	2.036 (4)
Y1—O2	2.163 (5)	O4—Y2^vi	2.036 (4)
Y1—O2^iii	2.163 (5)	O4—Rb1^x	3.084 (5)
Y1—O2^xi	2.163 (4)	O4—Rb2^xiv	3.473 (7)
O1^i—Rb1—O1^ii	97.70 (12)	O3^vi—Rb2—O4^vi	44.63 (12)
O1^i—Rb1—O1	97.70 (12)	O3^vii—Rb2—O4^vi	50.33 (13)
O1^ii—Rb1—O1	97.70 (12)	O3^viii—Rb2—O4^vi	106.52 (11)
O1^i—Rb1—O4^iii	150.98 (13)	O2^i—Rb2—O4^vi	75.66 (13)
O1^ii—Rb1—O4^iii	102.63 (13)	O2^ii—Rb2—O4^vi	122.45 (11)
O1—Rb1—O4^iii	99.82 (14)	O2—Rb2—O4^vi	143.79 (11)
O1^i—Rb1—O4^iv	102.63 (13)	O4^i—Rb2—O4^vi	48.39 (16)
O1^ii—Rb1—O4^iv	99.82 (15)	O4—Rb2—O4^vi	100.48 (2)
O1—Rb1—O4^iv	150.98 (13)	O4^ii—Rb2—O4^vi	130.93 (9)
O4^iii—Rb1—O4^iv	53.77 (14)	O3^vi—Rb2—O4^viii	50.33 (13)
O1^i—Rb1—O4^v	99.82 (15)	O3^vii—Rb2—O4^viii	106.52 (11)
O1^ii—Rb1—O4^v	150.98 (13)	O3^viii—Rb2—O4^viii	44.63 (12)
O1—Rb1—O4^v	102.63 (13)	O2^i—Rb2—O4^viii	122.45 (11)
O4^iii—Rb1—O4^v	53.77 (14)	O2^ii—Rb2—O4^viii	143.79 (11)
O4^iv—Rb1—O4^v	53.77 (14)	O2—Rb2—O4^viii	75.66 (13)
O1^i—Rb1—O2^iii	158.42 (12)	O4^i—Rb2—O4^viii	130.93 (9)
O1^ii—Rb1—O2^iii	60.72 (12)	O4—Rb2—O4^viii	48.39 (16)
O1—Rb1—O2^iii	85.65 (12)	O4^ii—Rb2—O4^viii	100.48 (2)
O4^iii—Rb1—O2^iii	46.70 (12)	O4^vi—Rb2—O4^viii	84.31 (12)
O4^iv—Rb1—O2^iii	83.01 (15)	O3^vi—Rb2—O4^vii	106.52 (11)
O4^v—Rb1—O2^iii	100.21 (14)	O3^vii—Rb2—O4^vii	44.63 (12)
O1^i—Rb1—O2^v	85.65 (12)	O3^viii—Rb2—O4^vii	50.33 (13)
O1^ii—Rb1—O2^v	158.42 (12)	O2^i—Rb2—O4^vii	143.79 (11)
O1—Rb1—O2^v	60.72 (12)	O2^ii—Rb2—O4^vii	75.66 (13)
O4^iii—Rb1—O2^v	83.01 (15)	O2—Rb2—O4^vii	122.45 (11)
O4^iv—Rb1—O2^v	100.21 (14)	O4^i—Rb2—O4^vii	100.48 (3)
O4^v—Rb1—O2^v	46.70 (12)	O4—Rb2—O4^vii	130.93 (9)
O2^iii—Rb1—O2^v	114.14 (7)	O4^ii—Rb2—O4^vii	48.39 (16)
O1^i—Rb1—O2^iv	60.72 (12)	O4^vi—Rb2—O4^vii	84.31 (12)
O1^ii—Rb1—O2^iv	85.65 (12)	O4^viii—Rb2—O4^vii	84.31 (12)
O1—Rb1—O2^iv	158.42 (12)	O1^ix—Y1—O1^ii	93.89 (17)
O4^iii—Rb1—O2^iv	100.21 (14)	O1^ix—Y1—O1^x	93.89 (17)
O4^iv—Rb1—O2^iv	46.70 (12)	O1^ii—Y1—O1^x	93.89 (17)
O4^v—Rb1—O2^iv	83.01 (15)	O1^ix—Y1—O2	174.29 (19)
O2^iii—Rb1—O2^iv	114.14 (7)	O1^ii—Y1—O2	84.32 (19)
O2^v—Rb1—O2^iv	114.14 (7)	O1^x—Y1—O2	91.64 (18)
O1^i—Rb1—O2^i	45.41 (11)	O1^ix—Y1—O2^iii	84.32 (19)
O1^ii—Rb1—O2^i	112.12 (13)	O1^ii—Y1—O2^iii	91.64 (18)
O1—Rb1—O2^i	53.95 (11)	O1^x—Y1—O2^iii	174.29 (19)
O4^iii—Rb1—O2^i	138.06 (15)	O2—Y1—O2^iii	90.31 (18)
O4^iv—Rb1—O2^i	135.97 (15)	O1^ix—Y1—O2^xi	91.64 (18)
O4^v—Rb1—O2^i	96.62 (12)	O1^ii—Y1—O2^xi	174.29 (19)
O2^iii—Rb1—O2^i	138.82 (9)	O1^x—Y1—O2^xi	84.32 (19)
O2^v—Rb1—O2^i	56.24 (17)	O2—Y1—O2^xi	90.31 (18)
O2^iv—Rb1—O2^i	105.000 (13)	O2^iii—Y1—O2^xi	90.31 (18)
O1^i—Rb1—O2^ii	53.95 (11)	O4^xiii—Y2—O4^xiv	86.5 (2)
O1^ii—Rb1—O2^ii	45.41 (11)	O4^xiii—Y2—O4^xv	86.5 (2)
O1—Rb1—O2^ii	112.12 (13)	O4^xiv—Y2—O4^xv	86.5 (2)
O4^iii—Rb1—O2^ii	135.97 (15)	O4^xiii—Y2—O3^xi	172.3 (2)
O4^iv—Rb1—O2^ii	96.62 (12)	O4^xiv—Y2—O3^xi	86.09 (19)
O4^v—Rb1—O2^ii	138.06 (15)	O4^xv—Y2—O3^xi	95.2 (2)
O2^iii—Rb1—O2^ii	105.000 (13)	O4^xiii—Y2—O3	86.09 (19)
O2^v—Rb1—O2^ii	138.82 (9)	O4^xiv—Y2—O3	95.2 (2)
O2^iv—Rb1—O2^ii	56.24 (17)	O4^xv—Y2—O3	172.3 (2)
O2^i—Rb1—O2^ii	85.95 (12)	O3^xi—Y2—O3	92.50 (18)
O1^i—Rb1—O2	112.12 (13)	O4^xiii—Y2—O3^iii	95.2 (2)
O1^ii—Rb1—O2	53.95 (11)	O4^xiv—Y2—O3^iii	172.3 (2)
O1—Rb1—O2	45.41 (11)	O4^xv—Y2—O3^iii	86.09 (19)
O4^iii—Rb1—O2	96.62 (12)	O3^xi—Y2—O3^iii	92.50 (18)
O4^iv—Rb1—O2	138.06 (15)	O3—Y2—O3^iii	92.50 (18)
O4^v—Rb1—O2	135.97 (15)	O1—P—O2	109.4 (3)
O2^iii—Rb1—O2	56.24 (17)	O1—P—O4	110.0 (3)
O2^v—Rb1—O2	105.000 (13)	O2—P—O4	107.6 (3)
O2^iv—Rb1—O2	138.82 (9)	O1—P—O3	110.4 (3)
O2^i—Rb1—O2	85.95 (12)	O2—P—O3	110.4 (3)
O2^ii—Rb1—O2	85.95 (12)	O4—P—O3	108.8 (3)
O3^vi—Rb2—O3^vii	91.50 (12)	P—O1—Ti1^v	151.0 (3)
O3^vi—Rb2—O3^viii	91.50 (12)	P—O1—Y1^v	151.0 (3)
O3^vii—Rb2—O3^viii	91.50 (12)	P—O1—Rb1	110.5 (2)
O3^vi—Rb2—O2^i	79.79 (14)	Ti1^v—O1—Rb1	97.47 (15)
O3^vii—Rb2—O2^i	100.68 (12)	Y1^v—O1—Rb1	97.47 (15)
O3^viii—Rb2—O2^i	165.13 (13)	P—O1—Rb2	77.95 (19)
O3^vi—Rb2—O2^ii	165.13 (13)	Ti1^v—O1—Rb2	103.84 (15)
O3^vii—Rb2—O2^ii	79.79 (14)	Y1^v—O1—Rb2	103.84 (15)
O3^viii—Rb2—O2^ii	100.68 (12)	Rb1—O1—Rb2	73.28 (10)
O2^i—Rb2—O2^ii	89.94 (14)	P—O2—Y1	153.6 (3)
O3^vi—Rb2—O2	100.68 (12)	P—O2—Rb1^x	89.7 (2)
O3^vii—Rb2—O2	165.13 (13)	Y1—O2—Rb1^x	92.73 (17)
O3^viii—Rb2—O2	79.79 (14)	P—O2—Rb2	90.2 (2)
O2^i—Rb2—O2	89.94 (13)	Y1—O2—Rb2	115.11 (17)
O2^ii—Rb2—O2	89.94 (14)	Rb1^x—O2—Rb2	100.54 (14)
O3^vi—Rb2—O4^i	82.25 (13)	P—O2—Rb1	93.9 (2)
O3^vii—Rb2—O4^i	56.59 (12)	Y1—O2—Rb1	86.81 (15)
O3^viii—Rb2—O4^i	147.05 (12)	Rb1^x—O2—Rb1	172.95 (16)
O2^i—Rb2—O4^i	44.08 (11)	Rb2—O2—Rb1	73.39 (11)
O2^ii—Rb2—O4^i	82.89 (12)	P—O3—Y2	137.5 (3)
O2—Rb2—O4^i	133.15 (12)	P—O3—Rb2^xiv	108.8 (3)
O3^vi—Rb2—O4	56.59 (12)	Y2—O3—Rb2^xiv	102.50 (17)
O3^vii—Rb2—O4	147.05 (13)	P—O4—Ti2^vi	172.4 (3)
O3^viii—Rb2—O4	82.25 (13)	P—O4—Y2^vi	172.4 (3)
O2^i—Rb2—O4	82.89 (12)	P—O4—Rb1^x	91.3 (2)
O2^ii—Rb2—O4	133.15 (12)	Ti2^vi—O4—Rb1^x	96.25 (18)
O2—Rb2—O4	44.08 (11)	Y2^vi—O4—Rb1^x	96.25 (18)
O4^i—Rb2—O4	119.18 (2)	P—O4—Rb2	86.8 (2)
O3^vi—Rb2—O4^ii	147.05 (13)	Ti2^vi—O4—Rb2	92.8 (2)
O3^vii—Rb2—O4^ii	82.25 (13)	Y2^vi—O4—Rb2	92.8 (2)
O3^viii—Rb2—O4^ii	56.59 (12)	Rb1^x—O4—Rb2	99.72 (16)
O2^i—Rb2—O4^ii	133.15 (12)	P—O4—Rb2^xiv	89.7 (3)
O2^ii—Rb2—O4^ii	44.08 (11)	Ti2^vi—O4—Rb2^xiv	88.62 (19)
O2—Rb2—O4^ii	82.89 (12)	Y2^vi—O4—Rb2^xiv	88.62 (19)
O4^i—Rb2—O4^ii	119.18 (2)	Rb1^x—O4—Rb2^xiv	96.60 (16)
O4—Rb2—O4^ii	119.18 (2)	Rb2—O4—Rb2^xiv	163.36 (17)

Symmetry codes: (i) −z+3/2, −x+1, y+1/2; (ii) −y+1, z−1/2, −x+3/2; (iii) y−1/2, −z+3/2, −x+1; (iv) z−1/2, −x+1/2, −y+2; (v) x+1/2, −y+3/2, −z+2; (vi) −x+1/2, −y+2, z+1/2; (vii) −z+1, x+1/2, −y+5/2; (viii) y−1, z, x+1; (ix) z−1, x, y; (x) x−1/2, −y+3/2, −z+2; (xi) −z+1, x+1/2, −y+3/2; (xii) −x+1/2, −y+1, z−1/2; (xiii) −y+3/2, −z+2, x+1/2; (xiv) −x+1/2, −y+2, z−1/2; (xv) −z+3/2, −x+1, y−1/2; (xvi) −x+1, y+1/2, −z+3/2; (xvii) x, y, z−1.