Redetermination of katayamalite, KLi3Ca7Ti2(SiO3)12(OH)2

Andrade, M.B.; Doell, D.; Downs, R.T.; Yang, H.

doi:10.1107/S1600536813016620

inorganic compounds

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Volume 69| Part 7| July 2013| Page i41

https://doi.org/10.1107/S1600536813016620

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Redetermination of katayamalite, KLi₃Ca₇Ti₂(SiO₃)₁₂(OH)₂

Marcelo B. Andrade,^a ^* Donald Doell,^b Robert T. Downs ^a and Hexiong Yang ^a

^aDepartment of Geosciences, University of Arizona, 1040 E. 4th Street, Tucson, Arizona 85721-0077, USA, and ^b122 Dublin Street, Peterborough, Ontario, K9H 3A9, Canada
^*Correspondence e-mail: mabadean@terra.com.br

(Received 3 June 2013; accepted 14 June 2013; online 22 June 2013)

The crystal structure of katayamalite, ideally KLi₃Ca₇Ti₂(SiO₃)₁₂(OH)₂ (potassium trilithium heptacalcium dititanium dodecasilicate dihydroxide), was previously reported in triclinic symmetry (C-1), with isotropic displacement parameters for all atoms and without the H-atom position [Kato & Murakami (1985 ). Mineral. J. 12, 206–217]. The present study redetermines the katayamalite structure with monoclinic symmetry (space group C2/c) based on single-crystal X-ray diffraction data from a sample from the type locality, Iwagi Island, Ehime Prefecture, Japan, with anisotropic displacement parameters for all non-H atoms, and with the H atoms located by difference Fourier analysis. The structure of katayamalite contains a set of six-membered silicate rings interconnected by sheets of Ca atoms on one side and by an ordered mixture of Li, Ti and K atoms on the other side, forming layers which are stacked normal to (001). From the eight different metal sites, three are located on special positions, viz. one K and one Li atom on twofold rotation axes and one Ca atom on an inversion center. The Raman spectrum of kataymalite shows a band at 3678 cm⁻¹, similar to that observed for hydroxyl-amphiboles, indicating no or very weak hydrogen bonding.

Related literature

For previous work on katayamalite, see: Kato & Murakami (1985). For minerals isostructural with or similar to katayamalite, see: Dusmatov et al. (1975 ); Fleischer et al. (1976 ); Menchetti & Sabelli (1979 ); Baur & Kassner (1992 ); Pautov et al. (2010 ). For Raman spectroscopic measurements on cyclosilicates and amphyboles, see: Alvarez & Coy-Yll (1978 ); Hawthorne (1983 ); Kim et al. (1993 ); Yang & Evans (1996 ); Frost & Pinto (2007 ).

Experimental

Crystal data

KLi₃Ca₇Ti₂(SiO₃)₁₂(OH)₂
M_r = 1383.38
Monoclinic, C 2/c
a = 16.9093 (10) Å
b = 9.7287 (5) Å
c = 20.9019 (12) Å
β = 112.396 (3)°
V = 3179.1 (3) Å³
Z = 4
Mo Kα radiation
μ = 2.36 mm⁻¹
T = 293 K
0.06 × 0.05 × 0.05 mm

Data collection

Bruker X8 APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2007 ) T_min = 0.871, T_max = 0.891
26611 measured reflections
4873 independent reflections
3632 reflections with I > 2σ(I)
R_int = 0.052

Refinement

R[F² > 2σ(F²)] = 0.035
wR(F²) = 0.083
S = 1.01
4873 reflections
290 parameters
1 restraint
All H-atom parameters refined
Δρ_max = 0.83 e Å⁻³
Δρ_min = −0.56 e Å⁻³

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Xtal-Draw (Downs & Hall-Wallace, 2003 ); software used to prepare material for publication: publCIF (Westrip, 2010 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536813016620/wm2749sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536813016620/wm2749Isup2.hkl

checkCIF report

Comment top

Katayamalite, KLi₃Ca₇Ti₂(SiO₃)₁₂(OH)₂, belongs to the baratovite group of minerals, which includes katayamalite, aleksandrovite [KLi₃Ca₇Sn₂(SiO₃)₁₂F₂] (Pautov et al., 2010), and baratovite [KLi₃Ca₇Ti₂(SiO₃)₁₂F₂] (Dusmatov et al., 1975; Fleischer et al., 1976; Menchetti & Sabelli, 1979).

Kato & Murakami (1985) first described the structure of katayamalite with composition (K_0.89Na_0.11)Li₃Ca₇(Ti_1.95Fe_0.05)(Si₆O₁₈)₂(OH_1.76F_0.24) from Iwagi Island, Inland Sea, Ehime Prefecture, Japan, with triclinic symmetry in space group C1 and unit-cell parameters a = 9.721 (2) Å, b = 16.923 (3) Å, c = 19.942 (3) Å, α = 91.43 (10)°, β = 104.15 (11)°, γ = 89.94 (10)°. Baur & Kassner (1992), however, proposed that katayamalite is isostructural with baratovite and in fact is monoclinic (space group C2/c). By using the transformation matrix (0 1 0/ 1 0 0/ -0.5 -0.5 -1) from the triclinic to the monoclinic setting the unit-cell parameters become a = 16.923 (3) Å, b = 9.721 (2) Å, c = 20.909 (3) Å, α = 89.98 (10)°, β = 112.40 (10)°, γ = 89.94 (10)°. Recently, aleksandrovite, the Sn analogue of baratovite, was described by Pautov et al. (2010) in space group C2/c and with unit-cell parameters a = 17.01 (2) Å, b = 9.751 (6) Å, c = 21.00 (2) Å, β = 112.45 (8)°. The structure refinement of aleksandrovite has not been reported yet.

The crystal structure of katayamalite is characterized by layers of close-packed six-membered rings of SiO₄ tetrahedra (Figs. 1 and 3). There are six non-equivalent Si atoms in the structure. The silicate layers (T) are connected by sheets of Ca atoms on one side and by an ordered mixture of Li, Ti and K, on the other side, forming a sandwich (Fig. 4) of T–Ca–T–(Li,Ti,K) layers. The sandwiches, in turn, are stacked in an ABAC packing scheme. The layer of Ca atoms is similar to a brucite layer with its dangling H atoms. The silicate rings are centered by a K atom in one layer, and by an H atom in the other.

The Ca1, Ca2 and Ca3 atoms are eight coordinated and located on general positions while atom Ca4 is 8-coordinated and has 1 symmetry. Li1 lies on a 2-fold rotation axis and Li2 is at a general position; both are tetrahedrally coordinated. The Ti atom is 6-coordinated in form of an octahedron and lies on a general position. The K atom is located on a special position with twofold rotation symmetry; it is 12-coordinated within a distorted coordination environment.

The Si—O bridging bond lengths range from 1.622 (2) to 1.6367 (19) Å, while the Si—O non-bridging bond lengths range from 1.594 (2) to 1.617 (2) Å. The two mean values are 1.629 and 1.604 Å, respectively, while the overall Si—O mean bond lengths is 1.617 Å.

The O—Si—O angles of the six independent SiO₄ tetrahedra range from 101.60 (10)° to 114.59 (11)°; the smallest angle in each tetrahedron is the one involving two bridging oxygen atoms which are bonded to K. The bridging Si—O—Si angles range from 150.52 (15)° to 158.53 (15)° with a mean value of 154.6°.

The H atom was located by Fourier analysis; it exhibits a short O—H distance (0.68 Å). Also, the (O···O) distances are greater than 3.25 Å revealing no or only little hydrogen bonding interactions.

Fig. 5 displays the Raman spectrum of katayamalite. There have been numerous Raman spectroscopic measurements on a variety of structurally related cyclosilicates. A tentative assignement is made according to previous studies, including tourmalines (Alvarez & Coy-Yll, 1978), benitoite (Kim et al., 1993), and joaquinites (Frost & Pinto, 2007). The bands between 900 and 1000 cm^-1, and between 1000 and 1200 cm^-1 are attributable to the Si—O symmetric and anti-symmetric stretching modes, respectively. The strongest band at 570 cm^-1 is ascribable to the Si—O—Si bending. The bands below 500 cm^-1 are associated with lattice vibrational modes of Ca—O, Ti—O and K—O. The band at ~3678 cm^-1 results from the O—H stretching vibrations, indicating little or no hydrogen bonding (Hawthorne, 1983). The band position is quite comparable to that for other hydroxyl-amphyboles. In fact, the O—H configuration in katayamalite and hydroxyl-amphyboles are remarkably analogous (Figs. 1 and 2).

Related literature top

For previous work on katayamalite, see: Kato & Murakami (1985). For minerals isostructural with or similar to katayamalite, see: Dusmatov et al. (1975); Fleischer et al. (1976); Menchetti & Sabelli (1979); Baur & Kassner (1992); Pautov et al. (2010). For Raman spectroscopic measurements on cyclosilicates and amphyboles, see: Alvarez & Coy-Yll (1978); Hawthorne (1983); Kim et al. (1993); Yang & Evans (1996); Frost & Pinto (2007).

Experimental top

The katayamalite specimen used in this study is from the type locality, Iwagi Island, Inland Sea, Ehime Prefecture, Japan and is in the collection of the RRUFF project (deposition http://rruff.info/R120164). Its chemical composition was measured using a CAMECA SX100 electron microprobe (14 analysis points), yielding the empirical chemical formula, calculated on the basis of 38 anions, (K_0.89Na_0.12)_Σ_1.01Li_3.21(Ca_6.87Mn_0.04Ba_0.02)_Σ_6.93(Ti_1.79Zr_0.14Fe_0.04Sn_0.02)_Σ_1.99(SiO₃)₁₂(OH_1.55F_0.45). The Raman spectrum of katayamalite was collected from a randomly oriented crystal at 100% power on a Thermo Almega microRaman system, using a solid-state 532 nm laser, and a thermoelectrically cooled CCD detector. The laser is partially polarized with 4 cm^-1 resolution and a spot size of 1 µm.

Structure description top

For previous work on katayamalite, see: Kato & Murakami (1985). For minerals isostructural with or similar to katayamalite, see: Dusmatov et al. (1975); Fleischer et al. (1976); Menchetti & Sabelli (1979); Baur & Kassner (1992); Pautov et al. (2010). For Raman spectroscopic measurements on cyclosilicates and amphyboles, see: Alvarez & Coy-Yll (1978); Hawthorne (1983); Kim et al. (1993); Yang & Evans (1996); Frost & Pinto (2007).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Xtal-Draw (Downs & Hall-Wallace, 2003); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top

	Fig. 1. Six-membered silicate ring in katayamalite. Pink, red, and blue represent SiO₄ groups, oxygen and hydrogen atoms, respectively.
	Fig. 2. Six-membered silicate ring in tremolite (Yang & Evans, 1996). Pink, red, and blue represent SiO₄ groups, oxygen and hydrogen atoms, respectively.
	Fig. 3. Six-membered silicate rings in the packing of the structure of katayamalite. Pink represents SiO₄ groups.
	Fig. 4. The crystal structure of katayamalite with layers stacked normal to (001). The SiO₄ ring layers are connected by Ca atoms on one side and by Li, Ti and K atoms on other side. Pink, brown, green, orange and yellow represent SiO₄ groups, Ca, Li, Ti and K atoms, respectively. Displacements ellipsoids are drawn at the 99.999% probability level.
	Fig. 5. The Raman spectrum of katayamalite.

Potassium trilithium heptacalcium dititanium dodecasilicate dihydroxide top

Crystal data top

KLi₃Ca₇Ti₂(SiO₃)₁₂(OH)₂	F(000) = 2744
M_r = 1383.38	D_x = 2.890 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 5222 reflections
a = 16.9093 (10) Å	θ = 2.7–32.2°
b = 9.7287 (5) Å	µ = 2.36 mm⁻¹
c = 20.9019 (12) Å	T = 293 K
β = 112.396 (3)°	Block, colourless
V = 3179.1 (3) Å³	0.06 × 0.05 × 0.05 mm
Z = 4

Data collection top

Bruker X8 APEXII CCD diffractometer	4873 independent reflections
Radiation source: fine-focus sealed tube	3632 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.052
φ and ω scan	θ_max = 32.4°, θ_min = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 2007)	h = −25→25
T_min = 0.871, T_max = 0.891	k = −14→13
26611 measured reflections	l = −24→27

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.035	Hydrogen site location: difference Fourier map
wR(F²) = 0.083	All H-atom parameters refined
S = 1.01	w = 1/[σ²(F_o²) + (0.0414P)² + 0.7329P] where P = (F_o² + 2F_c²)/3
4873 reflections	(Δ/σ)_max = 0.001
290 parameters	Δρ_max = 0.83 e Å⁻³
1 restraint	Δρ_min = −0.56 e Å⁻³

Crystal data top

KLi₃Ca₇Ti₂(SiO₃)₁₂(OH)₂	V = 3179.1 (3) Å³
M_r = 1383.38	Z = 4
Monoclinic, C2/c	Mo Kα radiation
a = 16.9093 (10) Å	µ = 2.36 mm⁻¹
b = 9.7287 (5) Å	T = 293 K
c = 20.9019 (12) Å	0.06 × 0.05 × 0.05 mm
β = 112.396 (3)°

Data collection top

Bruker X8 APEXII CCD diffractometer	4873 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2007)	3632 reflections with I > 2σ(I)
T_min = 0.871, T_max = 0.891	R_int = 0.052
26611 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.035	1 restraint
wR(F²) = 0.083	All H-atom parameters refined
S = 1.01	Δρ_max = 0.83 e Å⁻³
4873 reflections	Δρ_min = −0.56 e Å⁻³
290 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
K	0.0000	0.07120 (12)	0.2500	0.0361 (3)
Li1	0.5000	0.0835 (7)	0.2500	0.0167 (15)
Li2	0.2458 (3)	0.3180 (5)	0.2486 (3)	0.0185 (11)
Ca1	0.22009 (3)	−0.07260 (5)	0.51311 (3)	0.01101 (12)
Ca2	0.14530 (3)	0.28347 (5)	0.50710 (3)	0.01108 (13)
Ca3	0.07248 (3)	0.63859 (5)	0.50005 (3)	0.01062 (12)
Ca4	0.0000	0.0000	0.5000	0.01050 (17)
Ti	0.33450 (3)	0.07041 (4)	0.25164 (3)	0.00591 (11)
Si1	0.61419 (4)	0.26505 (7)	0.36044 (4)	0.00846 (16)
Si2	0.43082 (4)	0.32346 (7)	0.35974 (4)	0.00856 (16)
Si3	0.36872 (4)	0.63501 (7)	0.35927 (4)	0.00838 (16)
Si4	0.49109 (4)	0.88012 (7)	0.36047 (4)	0.00828 (16)
Si5	0.67395 (4)	0.81556 (7)	0.35909 (4)	0.00837 (16)
Si6	0.73864 (4)	0.50791 (7)	0.36208 (4)	0.00839 (16)
O1	0.65854 (12)	0.40272 (18)	0.34511 (11)	0.0148 (4)
O2	0.65931 (12)	0.22314 (18)	0.44096 (11)	0.0123 (4)
O3	0.61303 (12)	0.14415 (18)	0.30807 (11)	0.0122 (4)
O4	0.51486 (12)	0.31007 (19)	0.34026 (11)	0.0139 (4)
O5	0.35276 (11)	0.23886 (18)	0.30523 (11)	0.0118 (4)
O6	0.45262 (12)	0.28303 (19)	0.43917 (11)	0.0143 (4)
O7	0.40985 (12)	0.48821 (18)	0.35090 (12)	0.0163 (5)
O8	0.27342 (12)	0.65293 (18)	0.30411 (11)	0.0133 (4)
O9	0.37854 (12)	0.65030 (19)	0.43848 (11)	0.0139 (4)
O10	0.42704 (12)	0.74837 (18)	0.34065 (11)	0.0139 (4)
O11	0.52072 (12)	0.92080 (18)	0.44086 (11)	0.0124 (4)
O12	0.44828 (11)	0.00452 (18)	0.30824 (11)	0.0117 (4)
O13	0.57262 (11)	0.82069 (19)	0.34535 (11)	0.0151 (4)
O14	0.72871 (12)	0.85392 (18)	0.43847 (11)	0.0136 (4)
O15	0.69498 (12)	0.90701 (18)	0.30395 (11)	0.0120 (4)
O16	0.69232 (13)	0.65696 (18)	0.34465 (11)	0.0153 (4)
O17	0.78572 (12)	0.47659 (18)	0.30994 (11)	0.0117 (4)
O18	0.80132 (12)	0.49800 (19)	0.44276 (11)	0.0127 (4)
O19	0.10128 (13)	0.0692 (2)	0.45750 (11)	0.0132 (4)
H1	0.097 (2)	0.074 (4)	0.4238 (11)	0.016*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
K	0.0352 (6)	0.0342 (6)	0.0410 (8)	0.000	0.0170 (6)	0.000
Li1	0.006 (3)	0.027 (4)	0.016 (4)	0.000	0.004 (3)	0.000
Li2	0.016 (2)	0.015 (2)	0.023 (3)	0.0026 (18)	0.006 (2)	−0.002 (2)
Ca1	0.0084 (2)	0.0101 (2)	0.0156 (4)	0.00000 (18)	0.0057 (2)	−0.0002 (2)
Ca2	0.0081 (2)	0.0104 (2)	0.0155 (4)	0.00035 (17)	0.0053 (2)	0.0002 (2)
Ca3	0.0079 (2)	0.0107 (2)	0.0142 (4)	−0.00007 (17)	0.0054 (2)	0.0002 (2)
Ca4	0.0072 (3)	0.0101 (3)	0.0142 (5)	0.0000 (2)	0.0042 (3)	−0.0008 (3)
Ti	0.00370 (18)	0.00629 (18)	0.0081 (3)	0.00022 (15)	0.00263 (19)	0.00032 (17)
Si1	0.0058 (3)	0.0092 (3)	0.0110 (5)	−0.0005 (2)	0.0040 (3)	−0.0009 (3)
Si2	0.0056 (3)	0.0091 (3)	0.0107 (5)	0.0001 (2)	0.0029 (3)	−0.0008 (3)
Si3	0.0052 (3)	0.0086 (3)	0.0108 (5)	−0.0002 (2)	0.0026 (3)	0.0000 (3)
Si4	0.0049 (3)	0.0096 (3)	0.0101 (5)	−0.0001 (2)	0.0027 (3)	0.0009 (3)
Si5	0.0065 (3)	0.0085 (3)	0.0112 (5)	0.0005 (2)	0.0046 (3)	0.0006 (3)
Si6	0.0068 (3)	0.0084 (3)	0.0112 (5)	−0.0003 (2)	0.0047 (3)	−0.0002 (3)
O1	0.0124 (9)	0.0130 (9)	0.0202 (13)	−0.0047 (7)	0.0076 (9)	0.0007 (8)
O2	0.0107 (9)	0.0143 (9)	0.0123 (12)	0.0003 (7)	0.0052 (9)	−0.0006 (8)
O3	0.0096 (8)	0.0130 (8)	0.0155 (12)	−0.0004 (7)	0.0065 (9)	−0.0036 (8)
O4	0.0069 (8)	0.0185 (9)	0.0176 (12)	0.0024 (7)	0.0060 (9)	0.0004 (8)
O5	0.0076 (8)	0.0130 (8)	0.0129 (12)	−0.0005 (7)	0.0022 (8)	−0.0018 (8)
O6	0.0125 (9)	0.0163 (9)	0.0144 (13)	−0.0010 (7)	0.0052 (9)	−0.0003 (8)
O7	0.0134 (9)	0.0088 (8)	0.0274 (14)	0.0025 (7)	0.0085 (10)	−0.0007 (8)
O8	0.0063 (8)	0.0139 (9)	0.0174 (13)	−0.0013 (7)	0.0021 (9)	0.0010 (8)
O9	0.0119 (9)	0.0163 (9)	0.0132 (13)	−0.0013 (7)	0.0045 (9)	0.0000 (8)
O10	0.0099 (9)	0.0154 (9)	0.0177 (12)	−0.0037 (7)	0.0067 (9)	0.0017 (8)
O11	0.0112 (9)	0.0134 (8)	0.0130 (12)	−0.0006 (7)	0.0050 (9)	−0.0009 (8)
O12	0.0068 (8)	0.0133 (9)	0.0149 (12)	0.0006 (7)	0.0042 (8)	0.0023 (8)
O13	0.0068 (8)	0.0172 (9)	0.0233 (13)	0.0018 (7)	0.0081 (9)	0.0004 (8)
O14	0.0128 (9)	0.0143 (9)	0.0133 (12)	0.0000 (7)	0.0045 (9)	−0.0004 (8)
O15	0.0128 (9)	0.0109 (8)	0.0144 (12)	0.0019 (7)	0.0074 (9)	0.0030 (7)
O16	0.0183 (10)	0.0103 (9)	0.0207 (13)	0.0038 (7)	0.0110 (10)	0.0005 (8)
O17	0.0124 (9)	0.0121 (8)	0.0146 (12)	0.0006 (7)	0.0092 (9)	0.0000 (7)
O18	0.0114 (9)	0.0155 (9)	0.0107 (12)	0.0008 (7)	0.0038 (9)	−0.0001 (8)
O19	0.0143 (9)	0.0152 (9)	0.0140 (15)	−0.0001 (7)	0.0059 (10)	−0.0008 (9)

Geometric parameters (Å, º) top

K—O13ⁱ	3.083 (2)	Si1—O4	1.6281 (19)
K—O13ⁱⁱ	3.083 (2)	Si2—O5	1.604 (2)
K—O4ⁱⁱ	3.117 (2)	Si2—O6	1.607 (2)
K—O4ⁱ	3.117 (2)	Si2—O4	1.626 (2)
K—O1ⁱⁱ	3.125 (2)	Si2—O7	1.6367 (19)
K—O1ⁱ	3.125 (2)	Si3—O8	1.594 (2)
K—O10ⁱⁱ	3.141 (2)	Si3—O9	1.607 (2)
K—O10ⁱ	3.141 (2)	Si3—O10	1.622 (2)
K—O7ⁱⁱ	3.142 (2)	Si3—O7	1.6269 (19)
K—O7ⁱ	3.142 (2)	Si4—O12^xi	1.606 (2)
K—O16ⁱ	3.207 (2)	Si4—O11	1.609 (2)
K—O16ⁱⁱ	3.207 (2)	Si4—O10	1.6266 (19)
Li1—O12ⁱⁱⁱ	1.910 (3)	Si4—O13	1.633 (2)
Li1—O12	1.910 (3)	Si5—O15	1.600 (2)
Li1—O3	1.925 (3)	Si5—O14	1.606 (2)
Li1—O3ⁱⁱⁱ	1.925 (3)	Si5—O16	1.6248 (19)
Li2—O15ⁱ	1.893 (6)	Si5—O13	1.6265 (19)
Li2—O8ⁱⁱ	1.904 (5)	Si6—O17	1.605 (2)
Li2—O5	1.906 (5)	Si6—O18	1.617 (2)
Li2—O17ⁱⁱⁱ	1.915 (5)	Si6—O16	1.6222 (19)
Ca1—O19	2.348 (2)	Si6—O1	1.6253 (19)
Ca1—O14^iv	2.3732 (19)	O1—K^xii	3.125 (2)
Ca1—O9^v	2.380 (2)	O2—Ca1^vi	2.3943 (19)
Ca1—O2^vi	2.3943 (19)	O2—Ca3^xiii	2.396 (2)
Ca1—O18ⁱ	2.462 (2)	O2—Ca1^xii	2.470 (2)
Ca1—O2ⁱ	2.469 (2)	O3—Tiⁱⁱⁱ	1.924 (2)
Ca2—O19	2.321 (2)	O4—K^xii	3.117 (2)
Ca2—O18^iv	2.3901 (19)	O6—Ca3^xiii	2.395 (2)
Ca2—O14^iv	2.403 (2)	O6—Ca2^v	2.416 (2)
Ca2—O6^v	2.416 (2)	O6—Ca4^xii	2.4367 (19)
Ca2—O11ⁱ	2.432 (2)	O7—Ca4^xii	2.903 (2)
Ca2—O14ⁱ	2.462 (2)	O7—K^xii	3.142 (2)
Ca3—O6^vii	2.395 (2)	O8—Li2^xiv	1.904 (5)
Ca3—O2^vii	2.396 (2)	O8—Ti^xiv	1.9266 (19)
Ca3—O9^viii	2.397 (2)	O9—Ca1^v	2.380 (2)
Ca3—O18^iv	2.4094 (19)	O9—Ca3^viii	2.397 (2)
Ca3—O11^viii	2.414 (2)	O9—Ca4^xii	2.4490 (19)
Ca3—O11ⁱ	2.4414 (19)	O10—K^xii	3.141 (2)
Ca4—O19^ix	2.310 (2)	O11—Ca3^viii	2.414 (2)
Ca4—O19	2.310 (2)	O11—Ca2^xii	2.432 (2)
Ca4—O6ⁱ	2.4367 (19)	O11—Ca3^xii	2.4414 (19)
Ca4—O6^v	2.4367 (19)	O12—Si4^xv	1.606 (2)
Ca4—O9ⁱ	2.4490 (19)	O13—K^xii	3.083 (2)
Ca4—O9^v	2.4490 (19)	O14—Ca1^iv	2.3732 (19)
Ca4—O7ⁱ	2.903 (2)	O14—Ca2^iv	2.403 (2)
Ca4—O7^v	2.903 (2)	O14—Ca2^xii	2.462 (2)
Ti—O15^x	1.9195 (19)	O15—Li2^xii	1.893 (6)
Ti—O3ⁱⁱⁱ	1.924 (2)	O15—Ti^xvi	1.9195 (19)
Ti—O8ⁱⁱ	1.9266 (19)	O16—K^xii	3.207 (2)
Ti—O17ⁱ	1.9402 (19)	O17—Li2ⁱⁱⁱ	1.915 (5)
Ti—O5	1.9422 (19)	O17—Ti^xii	1.9402 (19)
Ti—O12	1.9436 (18)	O18—Ca2^iv	2.3901 (19)
Si1—O3	1.602 (2)	O18—Ca3^iv	2.4094 (19)
Si1—O2	1.613 (2)	O18—Ca1^xii	2.462 (2)
Si1—O1	1.6255 (19)	O19—H1	0.680 (18)

O12ⁱⁱⁱ—Li1—O12	132.6 (4)	O1—Si1—O4	103.60 (10)
O12ⁱⁱⁱ—Li1—O3	86.53 (8)	O5—Si2—O6	114.28 (11)
O12—Li1—O3	107.89 (9)	O5—Si2—O4	110.02 (11)
O12ⁱⁱⁱ—Li1—O3ⁱⁱⁱ	107.89 (9)	O6—Si2—O4	111.16 (11)
O12—Li1—O3ⁱⁱⁱ	86.53 (8)	O5—Si2—O7	109.76 (10)
O3—Li1—O3ⁱⁱⁱ	144.3 (4)	O6—Si2—O7	108.12 (11)
O15ⁱ—Li2—O8ⁱⁱ	136.3 (3)	O4—Si2—O7	102.86 (11)
O15ⁱ—Li2—O5	110.5 (3)	O8—Si3—O9	114.47 (11)
O8ⁱⁱ—Li2—O5	86.1 (2)	O8—Si3—O10	106.95 (11)
O15ⁱ—Li2—O17ⁱⁱⁱ	86.6 (2)	O9—Si3—O10	110.52 (11)
O8ⁱⁱ—Li2—O17ⁱⁱⁱ	111.4 (3)	O8—Si3—O7	111.97 (11)
O5—Li2—O17ⁱⁱⁱ	133.6 (3)	O9—Si3—O7	108.15 (11)
O15^x—Ti—O3ⁱⁱⁱ	89.64 (8)	O10—Si3—O7	104.31 (11)
O15^x—Ti—O8ⁱⁱ	90.65 (8)	O12^xi—Si4—O11	113.88 (10)
O3ⁱⁱⁱ—Ti—O8ⁱⁱ	90.97 (8)	O12^xi—Si4—O10	109.69 (10)
O15^x—Ti—O17ⁱ	85.19 (8)	O11—Si4—O10	111.83 (11)
O3ⁱⁱⁱ—Ti—O17ⁱ	173.77 (8)	O12^xi—Si4—O13	109.30 (11)
O8ⁱⁱ—Ti—O17ⁱ	92.55 (8)	O11—Si4—O13	109.83 (11)
O15^x—Ti—O5	174.56 (8)	O10—Si4—O13	101.60 (10)
O3ⁱⁱⁱ—Ti—O5	92.76 (8)	O15—Si5—O14	114.59 (11)
O8ⁱⁱ—Ti—O5	84.44 (8)	O15—Si5—O16	106.47 (11)
O17ⁱ—Ti—O5	92.69 (8)	O14—Si5—O16	109.69 (11)
O15^x—Ti—O12	93.66 (8)	O15—Si5—O13	111.35 (11)
O3ⁱⁱⁱ—Ti—O12	85.62 (8)	O14—Si5—O13	109.23 (11)
O8ⁱⁱ—Ti—O12	174.48 (8)	O16—Si5—O13	105.04 (11)
O17ⁱ—Ti—O12	91.24 (8)	O17—Si6—O18	113.54 (11)
O5—Ti—O12	91.39 (8)	O17—Si6—O16	109.83 (11)
O3—Si1—O2	113.90 (11)	O18—Si6—O16	110.86 (11)
O3—Si1—O1	110.90 (11)	O17—Si6—O1	108.67 (11)
O2—Si1—O1	110.09 (11)	O18—Si6—O1	110.52 (11)
O3—Si1—O4	106.12 (11)	O16—Si6—O1	102.88 (11)
O2—Si1—O4	111.69 (11)

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

Experimental details

Crystal data
Chemical formula	KLi₃Ca₇Ti₂(SiO₃)₁₂(OH)₂
M_r	1383.38
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	293
a, b, c (Å)	16.9093 (10), 9.7287 (5), 20.9019 (12)
β (°)	112.396 (3)
V (Å³)	3179.1 (3)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	2.36
Crystal size (mm)	0.06 × 0.05 × 0.05

Data collection
Diffractometer	Bruker X8 APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2007)
T_min, T_max	0.871, 0.891
No. of measured, independent and observed [I > 2σ(I)] reflections	26611, 4873, 3632
R_int	0.052
(sin θ/λ)_max (Å⁻¹)	0.754

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.035, 0.083, 1.01
No. of reflections	4873
No. of parameters	290
No. of restraints	1
H-atom treatment	All H-atom parameters refined
Δρ_max, Δρ_min (e Å⁻³)	0.83, −0.56

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), Xtal-Draw (Downs & Hall-Wallace, 2003), publCIF (Westrip, 2010).

Acknowledgements

The authors gratefully acknowledge the Arizona Science Foundation, and the Brazilian government (CNPq 202469/ 2011–5), for the funding support of this study.

References

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