Crystal structure of calcium perchlorate anhydrate, Ca(ClO₄)₂, from laboratory powder X-ray diffraction data

The crystal structure of anhydrous Ca(ClO₄)₂ crystallizes isotypically with Ca(AlD₄)₂.

Key indicators

• Powder X-ray study
• T = 295 K
• Mean [sigma](Cl-O) = 0.006 Å
• R factor = 0.000
• wR factor = 0.000
• Data-to-parameter ratio = 0.0

checkCIF/PLATON results

No syntax errors found



Alert level G
PLAT092_ALERT_4_G Check: Wavelength Given is not Cu,Ga,Mo,Ag,In Ka    1.54050 Ang.
PLAT142_ALERT_4_G s.u. on b - Axis Small or Missing ..............    0.00005 Ang.
PLAT143_ALERT_4_G s.u. on c - Axis Small or Missing ..............    0.00005 Ang.
PLAT981_ALERT_1_G No non-zero f" Anomalous Scattering Values Found     Please Check
PLAT986_ALERT_1_G No non-zero f' Anomalous Scattering Values Found     Please Check

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   0 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   5 ALERT level G = General information/check it is not something unexpected

   2 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
   0 ALERT type 3 Indicator that the structure quality may be low
   3 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: X'Pert Data Collector (PANalytical, 2011); cell refinement: GSAS (Larson & Von Dreele, 2000); data reduction: X'Pert HighScore Plus (PANalytical, 2011); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008) and CRYSTALS (Betteridge et al., 2003); program(s) used to refine structure: GSAS (Larson & Von Dreele, 2000); molecular graphics: ATOMS (Dowty, 2000); software used to prepare material for publication: GSAS (Larson & Von Dreele, 2000).

Calcium bis(perchlorate)

Crystal data

Ca(ClO4)2	Z = 8
Mr = 238.98	F(000) = 944.0
Orthorhombic, Pbca	Dx = 2.680 Mg m^−3
Hall symbol: -P_2ac_2ab	Cu Kα1 radiation, λ = 1.5405 Å
a = 13.75102 (8) Å	T = 295 K
b = 9.50887 (5) Å	white
c = 9.06168 (5) Å	flat_sheet, 24.9 × 24.9 mm
V = 1184.88 (1) Å^3	Specimen preparation: Prepared at 295 K

Data collection

PANalytical Empyrean diffractometer	Data collection mode: reflection
Radiation source: sealed X-ray tube, PANalytical Cu Ceramic X-ray tube	Scan method: step
Specimen mounting: packed powder	2θmin = 5.001°, 2θmax = 139.993°, 2θstep = 0.013°

Refinement

Least-squares matrix: full	Excluded region(s): 5 to 12.5 degrees are excluded due to background scattering at low angles, in addition there are no peaks in this region.
Rp = 0.068	Profile function: CW Profile function number 4 with 18 terms Pseudovoigt profile coefficients as parameterized in P. Thompson, D.E. Cox & J.B. Hastings (1987). J. Appl. Cryst.,20,79-83. Asymmetry correction of L.W. Finger, D.E. Cox & A. P. Jephcoat (1994). J. Appl. Cryst.,27,892-900. Microstrain broadening by P.W. Stephens, (1999). J. Appl. Cryst.,32,281-289. #1(GU) = 9.638 #2(GV) = -11.095 #3(GW) = 2.275 #4(GP) = 4.393 #5(LX) = 0.935 #6(ptec) = 0.00 #7(trns) = 0.00 #8(shft) = -4.2154 #9(sfec) = 0.00 #10(S/L) = 0.0005 #11(H/L) = 0.0005 #12(eta) = 0.7500 #13(S400 ) = 0.0E+00 #14(S040 ) = 0.0E+00 #15(S004 ) = 0.0E+00 #16(S220 ) = 0.0E+00 #17(S202 ) = 0.0E+00 #18(S022 ) = 0.0E+00 Peak tails are ignored where the intensity is below 0.0100 times the peak Aniso. broadening axis 0.0 0.0 1.0
Rwp = 0.104	44 parameters
Rexp = 0.055	0 restraints
R(F^2) = 0.15096	(Δ/σ)max = 0.04
10385 data points	Background function: GSAS Background function number 1 with 36 terms. Shifted Chebyshev function of 1st kind 1: 396.859 2: -606.961 3: 459.581 4: -240.760 5: 60.9683 6: 66.1787 7: -127.055 8: 123.403 9: -80.0454 10: 22.9955 11: 31.6319 12: -68.9521 13: 82.3967 14: -74.9306 15: 52.4628 16: -22.9755 17: -7.07207 18: 29.6007 19: -41.2483 20: 39.7866 21: -28.2300 22: 12.3296 23: 2.74056 24: -14.4441 25: 20.2978 26: -20.5325 27: 15.0728 28: -6.57858 29: -1.96745 30: 7.61710 31: -10.5263 32: 10.4139 33: -6.95249 34: 2.74624 35: 0.930279 36: -1.93129

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

	x	y	z	Uiso*/Ueq
Ca1	0.39788 (14)	0.5357 (2)	0.7164 (2)	0.0110 (2)*
Cl1	0.34080 (17)	0.6066 (3)	0.3157 (3)	0.0110 (2)*
Cl2	0.55928 (18)	0.7776 (3)	0.4961 (3)	0.0110 (2)*
O1	0.6154 (4)	0.7025 (6)	0.3850 (6)	0.0110 (2)*
O2	0.3176 (4)	0.7464 (6)	0.2773 (6)	0.0110 (2)*
O3	0.5240 (4)	0.6775 (7)	0.5973 (7)	0.0110 (2)*
O4	0.6137 (4)	0.8834 (6)	0.5773 (6)	0.0110 (2)*
O5	0.4842 (4)	0.8546 (7)	0.4199 (6)	0.0110 (2)*
O6	0.2815 (4)	0.5078 (6)	0.2414 (6)	0.0110 (2)*
O7	0.4359 (4)	0.5744 (6)	0.2647 (7)	0.0110 (2)*
O8	0.3387 (4)	0.5833 (6)	0.4708 (7)	0.0110 (2)*

Geometric parameters (Å, º)

Ca1—Cl1	3.776 (3)	Cl2—Ca1	3.769 (3)
Ca1—Cl1^i	3.605 (3)	Cl2—Ca1^v	3.808 (3)
Ca1—Cl1^ii	3.662 (3)	Cl2—Ca1^iii	3.596 (3)
Ca1—Cl1^iii	3.851 (3)	Cl2—Ca1^vii	3.627 (3)
Ca1—Cl2	3.769 (3)	Cl2—O1	1.456 (6)
Ca1—Cl2^i	3.808 (3)	Cl2—O3	1.408 (6)
Ca1—Cl2^iii	3.596 (3)	Cl2—O4	1.453 (6)
Ca1—Cl2^iv	3.627 (3)	Cl2—O5	1.442 (6)
Ca1—O1^iii	2.451 (6)	O1—Ca1^iii	2.451 (6)
Ca1—O2^i	2.412 (6)	O1—Cl2	1.456 (6)
Ca1—O3	2.448 (6)	O2—Ca1^v	2.412 (6)
Ca1—O4^iv	2.370 (6)	O2—Cl1	1.411 (6)
Ca1—O5^i	2.429 (6)	O3—Ca1	2.448 (6)
Ca1—O6^ii	2.512 (6)	O3—Cl2	1.408 (6)
Ca1—O7^iii	2.519 (6)	O4—Ca1^vii	2.370 (6)
Ca1—O8	2.413 (6)	O4—Cl2	1.453 (6)
Cl1—Ca1	3.776 (3)	O5—Ca1^v	2.429 (6)
Cl1—Ca1^v	3.605 (3)	O5—Cl2	1.442 (6)
Cl1—Ca1^vi	3.662 (3)	O6—Ca1^vi	2.512 (6)
Cl1—Ca1^iii	3.851 (3)	O6—Cl1	1.414 (6)
Cl1—O2	1.411 (6)	O7—Ca1^iii	2.519 (6)
Cl1—O6	1.414 (6)	O7—Cl1	1.421 (6)
Cl1—O7	1.421 (6)	O8—Ca1	2.413 (6)
Cl1—O8	1.423 (6)	O8—Cl1	1.423 (6)
O1^iii—Ca1—O2^i	147.7 (2)	O6^ii—Ca1—O8	77.5 (2)
O1^iii—Ca1—O3	113.4 (2)	O7^iii—Ca1—O8	116.53 (2)
O1^iii—Ca1—O5^i	135.9 (2)	O2—Cl1—O6	112.2 (4)
O1^iii—Ca1—O6^ii	79.0 (2)	O2—Cl1—O7	109.4 (4)
O1^iii—Ca1—O7^iii	73.10 (19)	O2—Cl1—O8	112.7 (4)
O1^iii—Ca1—O8	78.62 (18)	O6—Cl1—O7	103.5 (4)
O2^i—Ca1—O3	87.3 (2)	O6—Cl1—O8	110.8 (4)
O2^i—Ca1—O5^i	71.4 (2)	O7—Cl1—O8	107.8 (4)
O2^i—Ca1—O6^ii	70.80 (19)	O1—Cl2—O3	107.6 (4)
O2^i—Ca1—O7^iii	139.2 (2)	O1—Cl2—O4	114.6 (4)
O2^i—Ca1—O8	84.0 (2)	O1—Cl2—O5	107.3 (4)
O3—Ca1—O5^i	75.6 (2)	O3—Cl2—O4	108.4 (4)
O3—Ca1—O6^ii	145.7 (2)	O3—Cl2—O5	114.1 (4)
O3—Ca1—O7^iii	67.4 (2)	Ca1^iii—O1—Cl2	132.3 (4)
O3—Ca1—O8	74.3 (2)	Ca1^v—O2—Cl1	139.7 (4)
O5^i—Ca1—O6^ii	118.8 (2)	Ca1—O3—Cl2	154.6 (4)
O5^i—Ca1—O7^iii	71.6 (2)	Ca1^v—O5—Cl2	158.7 (4)
O5^i—Ca1—O8	141.7 (2)	Ca1^vi—O6—Cl1	135.9 (4)
O6^ii—Ca1—O7^iii	144.7 (2)	Ca1^iii—O7—Cl1	154.5 (4)

Symmetry codes: (i) x, −y+3/2, z+1/2; (ii) −x+1/2, −y+1, z+1/2; (iii) −x+1, −y+1, −z+1; (iv) −x+1, y−1/2, −z+3/2; (v) x, −y+3/2, z−1/2; (vi) −x+1/2, −y+1, z−1/2; (vii) −x+1, y+1/2, −z+3/2.