Revision of the structure of Cs₂CuSi₅O₁₂ leucite as orthorhombic Pbca

The crystal structure of a hydrothermally synthesized leucite analogue Cs₂CuSi₅O₁₂ has been determined and refined using the Rietveld method from high-resolution synchrotron X-ray and neutron powder diffraction data. This structure is based on the topology and cation-ordering scheme of the Pbca leucite structure of Cs₂CdSi₅O₁₂, and exhibits five ordered Si sites and one ordered Cu tetrahedrally coordinated (T) site. This structure for Cs₂CuSi₅O₁₂ is topologically identical to other known leucite structures and is different from that originally proposed by Heinrich & Baerlocher [(1991), Acta Cryst. C47, 237–241] in the tetragonal space group . The crystal structure of a dry-synthesized leucite analogue Cs₂CuSi₅O₁₂ has also been refined; this has the cubic pollucite structure with disordered T sites.

Computing details

(CS2CUSI5O12_T1_phase_1)

Crystal data

Cs2CuO12Si5	c = 13.62296 (4) Å
Mr = 661.77	V = 2512.85 (1) Å^3
Orthorhombic, Pbca	Z = 8
Hall symbol: -P 2ac 2ab	Dx = 3.499 Mg m^−3
a = 13.58943 (6) Å	T = 298 K
b = 13.57355 (5) Å

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

	x	y	z	Uiso*/Ueq
Cs1	0.13040 (18)	0.12954 (16)	0.14644 (12)	0.0127 (5)*
Cs2	0.3753 (2)	0.38635 (17)	0.38490 (13)	0.0335 (7)*
T1	0.3804 (2)	0.83732 (19)	0.93011 (18)	0.0120 (7)*
T2	0.1293 (4)	0.6742 (4)	0.5933 (3)	0.0212 (6)*
T3	0.5836 (4)	0.1213 (4)	0.6341 (3)	0.0212 (6)*
T4	0.6606 (4)	0.5915 (4)	0.1106 (3)	0.0212 (6)*
T5	0.9060 (4)	0.3788 (4)	0.8206 (3)	0.0212 (6)*
T6	0.8371 (4)	0.9088 (3)	0.3482 (4)	0.0212 (6)*
O1	0.4687 (4)	0.3522 (4)	0.1524 (4)	0.0180 (4)*
O2	0.1032 (4)	0.4874 (3)	0.4098 (4)	0.0180 (4)*
O3	0.3769 (4)	0.1611 (4)	0.4760 (3)	0.0180 (4)*
O4	0.7215 (4)	0.4220 (4)	0.6241 (4)	0.0180 (4)*
O5	0.6458 (4)	0.7090 (3)	0.3842 (3)	0.0180 (4)*
O6	0.3881 (4)	0.6268 (4)	0.7540 (3)	0.0180 (4)*
O7	0.9799 (4)	0.8952 (4)	0.6515 (4)	0.0180 (4)*
O8	0.6596 (4)	0.9729 (3)	0.8532 (4)	0.0180 (4)*
O9	0.9077 (4)	0.6430 (4)	0.9315 (3)	0.0180 (4)*
O10	0.2225 (4)	0.8818 (4)	0.1404 (4)	0.0180 (4)*
O11	0.1293 (4)	0.2013 (3)	0.9360 (3)	0.0180 (4)*
O12	0.8927 (4)	0.1427 (4)	0.2025 (3)	0.0180 (4)*

Geometric parameters (Å, º)

Cs1—O1^i	3.999 (6)	T1—O4^xv	1.945 (6)
Cs1—O2^ii	3.613 (5)	T1—O7^xvi	1.919 (5)
Cs1—O2^iii	3.793 (6)	T1—O9^xvii	1.940 (5)
Cs1—O3^iv	3.852 (6)	T1—O11^xviii	1.853 (5)
Cs1—O4^v	3.434 (5)	T2—O1^xix	1.597 (5)
Cs1—O5^vi	3.254 (6)	T2—O3^xviii	1.610 (5)
Cs1—O6^vii	3.626 (5)	T2—O5^xii	1.630 (5)
Cs1—O7^viii	3.152 (6)	T2—O10^xx	1.611 (5)
Cs1—O8^viii	3.175 (6)	T3—O1^xxi	1.622 (5)
Cs1—O9^viii	3.306 (6)	T3—O2^xxii	1.613 (5)
Cs1—O10^ix	3.589 (6)	T3—O6^xiii	1.574 (5)
Cs1—O11^x	3.028 (5)	T3—O11^xxiii	1.574 (5)
Cs1—O12^xi	3.324 (7)	T4—O2^xxiv	1.639 (5)
Cs2—O1	3.444 (6)	T4—O3^xxv	1.595 (5)
Cs2—O2	3.958 (6)	T4—O4^xiv	1.623 (5)
Cs2—O3	3.301 (6)	T4—O12^xxvi	1.604 (5)
Cs2—O4^viii	2.918 (6)	T5—O5^xxvii	1.634 (5)
Cs2—O5^viii	3.413 (5)	T5—O7^xxviii	1.612 (5)
Cs2—O6^viii	3.735 (7)	T5—O8^xxix	1.620 (5)
Cs2—O7^xii	3.326 (6)	T5—O12^xxi	1.645 (5)
Cs2—O8^xiii	3.786 (6)	T6—O6^xxx	1.629 (5)
Cs2—O9^xiv	3.043 (6)	T6—O8^xxxi	1.607 (5)
Cs2—O10^i	3.587 (6)	T6—O9^xxxii	1.645 (5)
Cs2—O11^ii	3.616 (7)	T6—O10^xxiv	1.606 (5)
Cs2—O12^iv	3.523 (6)
O4^xxxiii—T1—O7^xxxiv	92.3 (2)	O5^xxvii—T5—O7^xlii	112.9 (4)
O4^xxxiii—T1—O9^xxxv	115.1 (3)	O5^xxvii—T5—O8^xxix	101.1 (3)
O4^xxxiii—T1—O11^xviii	123.7 (3)	O5^xxvii—T5—O12^xxi	110.0 (4)
O7^xxxiv—T1—O9^xxxv	111.8 (3)	O7^xlii—T5—O8^xxix	110.9 (4)
O7^xxxiv—T1—O11^xviii	118.9 (3)	O7^xlii—T5—O12^xxi	111.1 (4)
O9^xxxv—T1—O11^xviii	96.3 (3)	O8^xxix—T5—O12^xxi	110.4 (4)
O1^xix—T2—O3^xviii	115.6 (4)	O6^xliii—T6—O8^xxxi	108.7 (4)
O1^xix—T2—O5^xxxvi	103.8 (4)	O6^xliii—T6—O9^xxxii	102.4 (4)
O1^xix—T2—O10^xx	110.4 (4)	O6^xliii—T6—O10^xl	115.3 (4)
O3^xviii—T2—O5^xxxvi	107.6 (4)	O8^xxxi—T6—O9^xxxii	112.4 (4)
O3^xviii—T2—O10^xx	112.6 (4)	O8^xxxi—T6—O10^xl	104.6 (4)
O5^xxxvi—T2—O10^xx	106.0 (4)	O9^xxxii—T6—O10^xl	113.6 (4)
O1^xxi—T3—O2^xxxvii	114.7 (4)	T2^vii—O1—T3^ii	140.8 (4)
O1^xxi—T3—O6^xxxviii	94.3 (3)	T3^xxx—O2—T4^xxiii	143.5 (4)
O1^xxi—T3—O11^xxxix	108.6 (4)	T2^i—O3—T4^xv	141.6 (4)
O2^xxxvii—T3—O6^xxxviii	111.3 (4)	T1^xxxviii—O4—T4^xxvii	126.4 (4)
O2^xxxvii—T3—O11^xxxix	110.0 (4)	T2^xliii—O5—T5^xiv	138.6 (4)
O6^xxxviii—T3—O11^xxxix	117.3 (4)	T3^xxxiii—O6—T6^xxxvi	156.5 (4)
O2^xl—T4—O3^xli	103.5 (4)	T1^xxxix—O7—T5^xliv	139.3 (4)
O2^xl—T4—O4^xiv	113.1 (4)	T5^xxvi—O8—T6^xlv	142.3 (5)
O2^xl—T4—O12^xxvi	106.9 (4)	T1^xlvi—O9—T6^xx	128.1 (4)
O3^xli—T4—O4^xiv	117.8 (4)	T2^xxxii—O10—T6^xxiii	155.3 (5)
O3^xli—T4—O12^xxvi	100.2 (4)	T1^i—O11—T3^xxxiv	129.3 (4)
O4^xiv—T4—O12^xxvi	114.0 (4)	T4^xxix—O12—T5^ii	137.4 (5)

Symmetry codes: (i) −x+1/2, y−1/2, z; (ii) x, −y+1/2, z−1/2; (iii) −x, y−1/2, −z+1/2; (iv) x−1/2, y, −z+1/2; (v) x−1/2, −y+1/2, −z+1; (vi) −x+1, y−1/2, −z+1/2; (vii) −x+1/2, −y+1, z−1/2; (viii) −x+1, −y+1, −z+1; (ix) x, y−1, z; (x) x, y, z−1; (xi) x−1, y, z; (xii) x−1/2, −y+3/2, −z+1; (xiii) −x+1, y−1/2, −z+3/2; (xiv) −x+3/2, −y+1, z−1/2; (xv) −x+1, y+1/2, −z+3/2; (xvi) x−1/2, y, −z+3/2; (xvii) x−1/2, −y+3/2, −z+2; (xviii) −x+1/2, y+1/2, z; (xix) −x+1/2, −y+1, z+1/2; (xx) x, −y+3/2, z+1/2; (xxi) x, −y+1/2, z+1/2; (xxii) x+1/2, −y+1/2, −z+1; (xxiii) x+1/2, y, −z+3/2; (xxiv) x+1/2, y, −z+1/2; (xxv) −x+1, y+1/2, −z+1/2; (xxvi) −x+3/2, y+1/2, z; (xxvii) −x+3/2, −y+1, z+1/2; (xxviii) −x+2, y−1/2, −z+3/2; (xxix) −x+3/2, y−1/2, z; (xxx) x+1/2, −y+3/2, −z+1; (xxxi) −x+3/2, −y+2, z−1/2; (xxxii) x, −y+3/2, z−1/2; (xxxiii) −x+1, y+3/2, −z+5/2; (xxxiv) x+1/2, y, −z+5/2; (xxxv) x+1/2, −y+5/2, −z+2; (xxxvi) x+1/2, −y+5/2, −z+1; (xxxvii) x+3/2, −y+3/2, −z+1; (xxxviii) −x+1, y+1/2, −z+5/2; (xxxix) x+3/2, y, −z+5/2; (xl) x+3/2, y, −z+3/2; (xli) −x+1, y+3/2, −z+3/2; (xlii) −x+2, y+1/2, −z+5/2; (xliii) x+3/2, −y+5/2, −z+1; (xliv) −x+2, y+3/2, −z+5/2; (xlv) −x+3/2, −y+2, z+1/2; (xlvi) x+3/2, −y+5/2, −z+2.