Cd3[Si3O9] (tricadmium trisilicate) crystallizes in the monoclinic space group P21/c and is isotypic with the mineral parawollastonite, Ca3[Si3O9]-2M. The structure contains distorted CdO6 octahedra and SiO4 tetrahedra that are organized in unbranched dreier single chains with three SiO4 tetrahedra in the repeat unit. All atoms occupy general positions 4e.
Supporting information
Key indicators
- Single-crystal X-ray study
- T = 273 K
- Mean (Si-O) = 0.002 Å
- R factor = 0.023
- wR factor = 0.064
- Data-to-parameter ratio = 17.6
checkCIF/PLATON results
No syntax errors found
Alert level C
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low ....... 0.98
PLAT062_ALERT_4_C Rescale T(min) & T(max) by ..................... 1.03
0 ALERT level A = In general: serious problem
0 ALERT level B = Potentially serious problem
2 ALERT level C = Check and explain
0 ALERT level G = General alerts; check
0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
0 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
Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT; program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ATOMS (Dowty, 2004); software used to prepare material for publication: SHELXL97.
tricadmium trisilicate
top
Crystal data top
Cd3[Si3O9] | F(000) = 1032 |
Mr = 565.47 | Dx = 4.962 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 4479 reflections |
a = 6.9463 (8) Å | θ = 2.7–31.2° |
b = 7.2563 (9) Å | µ = 8.86 mm−1 |
c = 15.0697 (18) Å | T = 293 K |
β = 94.791 (2)° | Plate, colourless |
V = 756.93 (16) Å3 | 0.26 × 0.14 × 0.02 mm |
Z = 4 | |
Data collection top
Bruker APEX CCD diffractometer | 2412 independent reflections |
Radiation source: fine-focus sealed tube | 1980 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.037 |
ω scans | θmax = 31.2°, θmin = 2.7° |
Absorption correction: multi-scan (SADABS; Bruker, 2002) | h = −8→9 |
Tmin = 0.203, Tmax = 0.816 | k = −10→10 |
8622 measured reflections | l = −21→19 |
Refinement top
Refinement on F2 | Primary atom site location: isomorphous structure methods |
Least-squares matrix: full | w = 1/[σ2(Fo2) + (0.0215P)2 + 1.0847P] where P = (Fo2 + 2Fc2)/3 |
R[F2 > 2σ(F2)] = 0.024 | (Δ/σ)max = 0.001 |
wR(F2) = 0.064 | Δρmax = 1.60 e Å−3 |
S = 1.07 | Δρmin = −1.38 e Å−3 |
2412 reflections | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
137 parameters | Extinction coefficient: 0.00358 (19) |
0 restraints | |
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 | Uiso*/Ueq | |
Cd1 | 0.01235 (2) | 0.37607 (2) | 0.248498 (10) | 0.00866 (7) | |
Cd2 | 0.24957 (3) | 0.62788 (2) | 0.098674 (12) | 0.00993 (7) | |
Cd3 | 0.25370 (2) | 0.11992 (2) | 0.101523 (12) | 0.00989 (7) | |
Si1 | 0.23852 (9) | 0.16124 (8) | 0.41008 (4) | 0.00760 (12) | |
Si2 | 0.23940 (9) | 0.59016 (8) | 0.41056 (4) | 0.00734 (12) | |
Si3 | 0.54611 (9) | 0.37667 (7) | 0.19864 (4) | 0.00723 (12) | |
O1 | 0.0431 (3) | 0.1232 (2) | 0.34626 (15) | 0.0103 (4) | |
O2 | 0.0428 (3) | 0.6305 (2) | 0.34907 (15) | 0.0109 (4) | |
O3 | 0.2259 (3) | 0.3799 (2) | 0.01320 (14) | 0.0131 (4) | |
O4 | 0.2314 (3) | 0.6289 (2) | 0.51484 (14) | 0.0132 (4) | |
O5 | 0.2977 (3) | 0.37608 (19) | 0.40041 (12) | 0.0137 (3) | |
O6 | 0.3173 (3) | 0.3745 (2) | 0.20452 (14) | 0.0106 (4) | |
O7 | 0.4167 (2) | 0.0551 (2) | 0.36594 (11) | 0.0121 (3) | |
O8 | 0.5842 (2) | 0.1982 (2) | 0.13334 (11) | 0.0120 (3) | |
O9 | 0.6954 (3) | 0.3759 (2) | 0.28588 (13) | 0.0100 (4) | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
Cd1 | 0.00874 (11) | 0.00846 (11) | 0.00886 (12) | −0.00002 (4) | 0.00115 (8) | 0.00004 (4) |
Cd2 | 0.01053 (11) | 0.00889 (10) | 0.01051 (11) | 0.00156 (5) | 0.00171 (7) | 0.00156 (5) |
Cd3 | 0.00982 (11) | 0.00962 (10) | 0.01035 (11) | −0.00154 (5) | 0.00142 (7) | −0.00174 (5) |
Si1 | 0.0080 (3) | 0.0077 (2) | 0.0070 (3) | 0.00052 (19) | −0.0003 (2) | −0.0002 (2) |
Si2 | 0.0082 (3) | 0.0073 (2) | 0.0064 (3) | −0.00049 (19) | −0.0005 (2) | −0.00004 (19) |
Si3 | 0.0064 (3) | 0.0077 (2) | 0.0075 (3) | −0.00001 (18) | 0.0000 (2) | −0.00018 (19) |
O1 | 0.0089 (9) | 0.0137 (9) | 0.0084 (9) | −0.0008 (6) | 0.0005 (7) | −0.0009 (6) |
O2 | 0.0090 (9) | 0.0141 (9) | 0.0093 (9) | −0.0012 (6) | 0.0000 (7) | 0.0020 (6) |
O3 | 0.0202 (10) | 0.0125 (8) | 0.0067 (9) | 0.0006 (6) | 0.0010 (7) | −0.0011 (6) |
O4 | 0.0235 (11) | 0.0107 (8) | 0.0053 (8) | −0.0003 (6) | 0.0012 (7) | −0.0007 (6) |
O5 | 0.0182 (8) | 0.0067 (7) | 0.0165 (8) | 0.0005 (5) | 0.0044 (6) | 0.0000 (5) |
O6 | 0.0058 (8) | 0.0162 (8) | 0.0099 (8) | −0.0009 (6) | 0.0004 (6) | −0.0008 (6) |
O7 | 0.0110 (7) | 0.0100 (6) | 0.0150 (8) | 0.0020 (5) | −0.0008 (6) | −0.0044 (6) |
O8 | 0.0105 (8) | 0.0104 (7) | 0.0149 (8) | 0.0017 (5) | 0.0001 (6) | −0.0047 (6) |
O9 | 0.0077 (8) | 0.0147 (8) | 0.0074 (8) | 0.0012 (6) | −0.0018 (6) | 0.0000 (6) |
Geometric parameters (Å, º) top
Cd1—O6 | 2.272 (2) | Si1—O1 | 1.620 (2) |
Cd1—O1i | 2.3045 (18) | Si1—O5 | 1.6219 (15) |
Cd1—O9ii | 2.317 (2) | Si1—O7 | 1.6447 (17) |
Cd1—O2iii | 2.3214 (19) | Si2—O4 | 1.602 (2) |
Cd1—O1 | 2.3519 (19) | Si2—O2 | 1.612 (2) |
Cd1—O2 | 2.3869 (19) | Si2—O5 | 1.6158 (15) |
Cd1—O5 | 2.9000 (18) | Si2—O8v | 1.6399 (17) |
Cd1—Cd2 | 3.4312 (3) | Si3—O6 | 1.599 (2) |
Cd1—Cd3 | 3.4338 (3) | Si3—O9 | 1.605 (2) |
Cd2—O4iv | 2.1681 (17) | Si3—O7v | 1.6529 (16) |
Cd2—O3 | 2.2113 (17) | Si3—O8 | 1.6611 (16) |
Cd2—O1i | 2.260 (2) | O1—Cd2iii | 2.260 (2) |
Cd2—O7v | 2.3939 (17) | O1—Cd1iii | 2.3045 (18) |
Cd2—O6 | 2.4538 (18) | O2—Cd3i | 2.249 (2) |
Cd2—O9v | 2.5102 (18) | O2—Cd1i | 2.3214 (19) |
Cd2—Si3 | 3.0524 (6) | O3—Si1vi | 1.592 (2) |
Cd3—O4vi | 2.2262 (17) | O4—Cd2ix | 2.1681 (17) |
Cd3—O2iii | 2.249 (2) | O4—Cd3viii | 2.2262 (17) |
Cd3—O3 | 2.3073 (17) | O7—Si3vii | 1.6529 (16) |
Cd3—O8 | 2.3743 (16) | O7—Cd2vii | 2.3939 (17) |
Cd3—O6 | 2.4293 (18) | O8—Si2vii | 1.6399 (17) |
Cd3—O9vii | 2.4573 (18) | O9—Cd1x | 2.317 (2) |
Cd3—Si3 | 3.0400 (6) | O9—Cd3v | 2.4573 (18) |
Si1—O3viii | 1.592 (2) | O9—Cd2vii | 2.5102 (18) |
| | | |
O6—Cd1—O1i | 86.27 (7) | O5—Si1—O7 | 102.06 (9) |
O6—Cd1—O9ii | 177.10 (5) | O4—Si2—O2 | 115.78 (11) |
O1i—Cd1—O9ii | 92.17 (7) | O4—Si2—O5 | 106.92 (9) |
O6—Cd1—O2iii | 85.40 (7) | O2—Si2—O5 | 109.09 (9) |
O1i—Cd1—O2iii | 101.21 (8) | O4—Si2—O8v | 113.60 (10) |
O9ii—Cd1—O2iii | 92.51 (7) | O2—Si2—O8v | 107.89 (10) |
O6—Cd1—O1 | 98.08 (7) | O5—Si2—O8v | 102.69 (9) |
O1i—Cd1—O1 | 175.573 (9) | O6—Si3—O9 | 122.12 (10) |
O9ii—Cd1—O1 | 83.45 (7) | O6—Si3—O7v | 104.20 (9) |
O2iii—Cd1—O1 | 78.43 (9) | O9—Si3—O7v | 111.27 (9) |
O6—Cd1—O2 | 98.85 (7) | O6—Si3—O8 | 103.48 (9) |
O1i—Cd1—O2 | 78.05 (9) | O9—Si3—O8 | 111.02 (9) |
O9ii—Cd1—O2 | 83.19 (7) | O7v—Si3—O8 | 102.80 (9) |
O2iii—Cd1—O2 | 175.598 (11) | Si1—O1—Cd2iii | 120.95 (12) |
O1—Cd1—O2 | 101.96 (8) | Si1—O1—Cd1iii | 126.08 (11) |
O4iv—Cd2—O3 | 108.98 (9) | Cd2iii—O1—Cd1iii | 97.49 (8) |
O4iv—Cd2—O1i | 102.47 (8) | Si1—O1—Cd1 | 105.46 (9) |
O3—Cd2—O1i | 100.15 (8) | Cd2iii—O1—Cd1 | 100.41 (8) |
O4iv—Cd2—O7v | 108.52 (7) | Cd1iii—O1—Cd1 | 102.54 (9) |
O3—Cd2—O7v | 88.49 (7) | Si2—O2—Cd3i | 123.97 (13) |
O1i—Cd2—O7v | 143.05 (7) | Si2—O2—Cd1i | 126.20 (11) |
O4iv—Cd2—O6 | 170.92 (7) | Cd3i—O2—Cd1i | 97.40 (8) |
O3—Cd2—O6 | 76.68 (7) | Si2—O2—Cd1 | 104.50 (9) |
O1i—Cd2—O6 | 83.08 (7) | Cd3i—O2—Cd1 | 98.56 (7) |
O7v—Cd2—O6 | 63.92 (6) | Cd1i—O2—Cd1 | 100.98 (9) |
O4iv—Cd2—O9v | 79.52 (6) | Si1vi—O3—Cd2 | 135.53 (10) |
O3—Cd2—O9v | 170.71 (7) | Si1vi—O3—Cd3 | 113.65 (8) |
O1i—Cd2—O9v | 81.13 (7) | Cd2—O3—Cd3 | 109.31 (9) |
O7v—Cd2—O9v | 85.14 (6) | Si2—O4—Cd2ix | 135.17 (10) |
O6—Cd2—O9v | 94.42 (7) | Si2—O4—Cd3viii | 115.28 (8) |
O4vi—Cd3—O2iii | 101.60 (8) | Cd2ix—O4—Cd3viii | 108.69 (9) |
O4vi—Cd3—O3 | 109.03 (8) | Si2—O5—Si1 | 148.03 (13) |
O2iii—Cd3—O3 | 97.36 (7) | Si3—O6—Cd1 | 166.24 (13) |
O4vi—Cd3—O8 | 109.34 (7) | Si3—O6—Cd3 | 95.78 (9) |
O2iii—Cd3—O8 | 145.24 (7) | Cd1—O6—Cd3 | 93.78 (6) |
O3—Cd3—O8 | 87.36 (7) | Si3—O6—Cd2 | 95.40 (9) |
O4vi—Cd3—O6 | 172.55 (7) | Cd1—O6—Cd2 | 93.04 (6) |
O2iii—Cd3—O6 | 83.41 (7) | Cd3—O6—Cd2 | 98.03 (7) |
O3—Cd3—O6 | 75.46 (7) | Si1—O7—Si3vii | 139.89 (11) |
O8—Cd3—O6 | 64.41 (6) | Si1—O7—Cd2vii | 123.65 (8) |
O4vi—Cd3—O9vii | 79.62 (6) | Si3vii—O7—Cd2vii | 96.20 (8) |
O2iii—Cd3—O9vii | 83.04 (7) | Si2vii—O8—Si3 | 140.61 (11) |
O3—Cd3—O9vii | 170.97 (7) | Si2vii—O8—Cd3 | 123.15 (8) |
O8—Cd3—O9vii | 87.25 (6) | Si3—O8—Cd3 | 96.15 (7) |
O6—Cd3—O9vii | 95.66 (7) | Si3—O9—Cd1x | 111.27 (11) |
O3viii—Si1—O1 | 115.83 (11) | Si3—O9—Cd3v | 127.52 (9) |
O3viii—Si1—O5 | 107.63 (9) | Cd1x—O9—Cd3v | 94.75 (6) |
O1—Si1—O5 | 108.44 (9) | Si3—O9—Cd2vii | 128.35 (9) |
O3viii—Si1—O7 | 114.32 (10) | Cd1x—O9—Cd2vii | 94.37 (6) |
O1—Si1—O7 | 107.54 (10) | Cd3v—O9—Cd2vii | 91.91 (7) |
Symmetry codes: (i) −x, y+1/2, −z+1/2; (ii) x−1, y, z; (iii) −x, y−1/2, −z+1/2; (iv) x, −y+3/2, z−1/2; (v) −x+1, y+1/2, −z+1/2; (vi) x, −y+1/2, z−1/2; (vii) −x+1, y−1/2, −z+1/2; (viii) x, −y+1/2, z+1/2; (ix) x, −y+3/2, z+1/2; (x) x+1, y, z. |