CaCu1.424Fe0.576Si2

Dai, Y.; Liu, Y.; Mihalkovic, M.; Wen, B.; Zhang, L.; Fan, C.

doi:10.1107/S2414314625003256

inorganic compounds

IUCrDATA

ISSN: 2414-3146

Volume 10| Part 4| April 2025| x250325

https://doi.org/10.1107/S2414314625003256

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CaCu_1.424Fe_0.576Si₂

Yangkun Dai,^a Yibo Liu,^a Marek Mihalkovic,^b Bin Wen,^a Lifeng Zhang ^a,^c and Changzeng Fan ^a,^d ^*

^aState Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, People's Republic of China, ^bInstitute of Physics, Slovak Academy of Sciences, 84511 Bratislava, Slovakia, ^cSchool of Mechanical and Materials Engineering, North China University of Technology, Beijing 100144, People's Republic of China, and ^dHebei Key Lab for Optimizing Metal Product Technology and Performance, Yanshan University, Qinhuangdao 066004, People's Republic of China
^*Correspondence e-mail: chzfan@ysu.edu.cn

Edited by M. Bolte, Goethe-Universität Frankfurt, Germany (Received 7 April 2025; accepted 10 April 2025; online 17 April 2025)

A CaCu_1.424Fe_0.576Si₂ phase was obtained during high-pressure sintering of an Si-rich quasicrystal composition prealloy with the nominal chemical composition Si₆₁Cu₃₀Ca₇Fe₂. The obtained phase crystallizes in the space group I4/mmm (No. 139), with a = b = 4.041 Å and c = 10.010 Å. It is isotypic with CaCu₂Si₂ (a = b = 4.06 Å and c = 9.91 Å) [Palenzona et al. (1986 ). J. Less-Common Met. 119, 199–209] and CaFe₂Si₂ (a = b = 3.94 Å and c = 10.19 Å) [Hlukhyy et al. (2012 ). Z. Anorg. Allg. Chem. 638, 1619–1619]. It features a co-occupancy of Cu and Fe atoms with a ratio of the refined site-occupancy factors of 0.71 (15):0.29 (15).

Keywords: crystal structure; high-pressure sintering; intermetallic; Cu-Fe co-occupation.

CCDC reference: 2442775

Structure description

It has been reported that Si-rich quasicrystals form under extreme conditions during atomic bomb explosion (Bindi et al., 2021 ). In this work, we took the Si-rich quasicrystal compostion and applied our high-pressure sintering methodology to reveal phases forming at this composition in a laboratory experiment and obtained crystals of the composition CaCu_1.424Fe_0.576Si₂. This phase shows remarkable structural similarities to BaFe_1.8Co_0.2As₂ (a = b = 3.96 Å and c = 13.96 Å) reported by Sefat et al. (2008 ), sharing identical space-group symmetry and analogous co-site-occupation behaviour. CaCu_1.424Fe_0.576Si₂, as well as BaFe_1.8Co_0.2As₂, and along with other AETX-type compounds (AE = alkaline earth metals, T = transition metals and X = Si, Ge, As), belong to the 122-type structure and all show the space group I4/mmm.

The distribution of atoms in the crystal unit of CaCu_1.424Fe_0.576Si₂ is illustrated in Fig. 1. The coordination environment of the Ca atom is shown in Fig. 2. The Ca1 atom is located in a position with 4/mmm symmetry (multiplicity 2, Wyckoff symbol a). It is surrounded by eight Si1 atoms (4mm, 4 e) and eight Cu1/Fe1 atoms ( $[\overline{4}]$ m2, 4 d), forming the centre of a tetradecahedron. The shortest distance between calcium and silicon is Ca1—Si1 = 3.087 (4) Å, whereas the longest Ca1—Cu1/Fe1 bond is 3.216 (2) Å.

Figure 1
The crystal structure of CaCu_1.424Fe_0.576Si₂ (one unit cell), with displacement ellipsoids drawn at the 99% probability level.

Figure 2
(a) The tetradecahedron formed around the Ca1 atom at the 2 a site and (b) the environment of the Ca1 atom, with displacement ellipsoids given at the 99% probability level. [Symmetry codes: (i) −x − $[{1\over 2}]$ , −y + $[{1\over 2}]$ , −z + $[{1\over 2}]$ ; (iii) −x + $[{1\over 2}]$ , −y + $[{1\over 2}]$ , −z + $[{1\over 2}]$ ; (xii) x − $[{1\over 2}]$ , y − $[{1\over 2}]$ , z − $[{1\over 2}]$ ; (xiii) −x − $[{1\over 2}]$ , −y − $[{1\over 2}]$ , −z + $[{1\over 2}]$ ; (xiv) x + $[{1\over 2}]$ , y + $[{1\over 2}]$ , z − $[{1\over 2}]$ ; (xv) −x + $[{1\over 2}]$ , −y − $[{1\over 2}]$ , −z + $[{1\over 2}]$ ; (xvi) x − $[{1\over 2}]$ , y + $[{1\over 2}]$ , z − $[{1\over 2}]$ ; (xvii) x + $[{1\over 2}]$ , y − $[{1\over 2}]$ , z − $[{1\over 2}]$ ; (xviii) −x, −y, −z.]

This study refined the crystal structure model of CaCu_1.424Fe_0.576Si₂based on single-crystal X-ray diffraction data. Its composition was confirmed by EDX results.

Synthesis and crystallization

High-purity elements Ca (99.5% purity, 0.068 g), Cu (99.5% purity, 0.4718 g), Fe (99.9% purity, 0.0247 g) and Si (99.5% purity, 0.4270 g) were weighed precisely according to a stoichiometric ratio of 7:30:2:61. The mixture was homogenized and thoroughly ground in an agate mortar. Subsequently, the blended powder was loaded into a tungsten carbide die with a 5 mm inner diameter and compacted at 6 MPa for 3 min to form cylindrical pellets. These pellets were subjected to high-pressure sintering experiments using a six-anvil apparatus (Liu & Fan, 2018 ), where samples were pressurized to 6 GPa and heated to 1573 K for 40 min, followed by rapid quenching to room temperature through furnace power termination. A regular specimen was selected and mounted on a glass fiber using adhesive for X-ray diffraction measurements.

Refinement

Comprehensive crystallographic data, data collection parameters and structure refinement details are summarized in Table 1. To facilitate comparative analysis, the labelling scheme and atomic coordinates for CaCu_1.424Fe_0.576Si₂ were taken from the corresponding data of CaCu₂Si₂ (Palenzona et al., 1986) and CaFe₂Si₂ (Hlukhyy et al., 2012). The sites of the occupancy factors for the co-occupancy of the Cu and Fe atoms refined to 0.71 (15) and 0.29 (15), respectively. The command `SHEL 999 0.84' was used to eliminate weakly diffracting high-angle data. The maximum and minimum residual electron densities in the final difference map are located at 0.99 Å from Ca1 and 0.00 Å from Cu1, respectively.

Table 1
Experimental details

Crystal data
Chemical formula	CaCu_1.42Fe_0.58Si₂
M_r	218.91
Crystal system, space group	Tetragonal, I4/mmm
Temperature (K)	296
a, c (Å)	4.041 (3), 10.010 (9)
V (Å³)	163.5 (3)
Z	2
Radiation type	Mo Kα
μ (mm⁻¹)	13.82
Crystal size (mm)	0.10 × 0.07 × 0.06

Data collection
Diffractometer	Bruker D8 Venture Photon 100 CMOS
Absorption correction	Multi-scan (SADABS; Krause et al., 2015 )
T_min, T_max	0.383, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections	707, 60, 46
R_int	0.097
(sin θ/λ)_max (Å⁻¹)	0.588

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.071, 0.156, 1.29
No. of reflections	60
No. of parameters	9
Δρ_max, Δρ_min (e Å⁻³)	1.05, −1.45
Computer programs: APEX5 (Bruker, 2023 ), SAINT (Bruker, 2023), SHELXT (Sheldrick, 2015a ), SHELXL (Sheldrick, 2015b ), DIAMOND (Brandenburg & Putz, 2017 ) and publCIF (Westrip, 2010 ).

Structural data

CCDC reference: 2442775

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2414314625003256/bt4168sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314625003256/bt4168Isup2.hkl

supplementary file. DOI: https://doi.org/10.1107/S2414314625003256/bt4168sup3.docx

checkCIF report

Computing details top

Calcium copper iron disilicide top

Crystal data top

CaCu_1.42Fe_0.58Si₂	D_x = 4.448 Mg m⁻³
M_r = 218.91	Mo Kα radiation, λ = 0.71073 Å
Tetragonal, I4/mmm	Cell parameters from 452 reflections
a = 4.041 (3) Å	θ = 4.1–26.9°
c = 10.010 (9) Å	µ = 13.82 mm⁻¹
V = 163.5 (3) Å³	T = 296 K
Z = 2	Lump, gray
F(000) = 209	0.10 × 0.07 × 0.06 mm

Data collection top

Bruker D8 Venture Photon 100 CMOS diffractometer	46 reflections with I > 2σ(I)
phi and ω scans	R_int = 0.097
Absorption correction: multi-scan (SADABS; Krause et al., 2015)	θ_max = 24.7°, θ_min = 4.1°
T_min = 0.383, T_max = 0.746	h = −4→4
707 measured reflections	k = −4→4
60 independent reflections	l = −11→11

Refinement top

Refinement on F²	9 parameters
Least-squares matrix: full	0 restraints
R[F² > 2σ(F²)] = 0.071	w = 1/[σ²(F_o²) + (0.0957P)²] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.156	(Δ/σ)_max < 0.001
S = 1.29	Δρ_max = 1.05 e Å⁻³
60 reflections	Δρ_min = −1.45 e Å⁻³

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
Fe1	0.000000	0.500000	0.250000	0.0171 (18)	0.29 (15)
Cu1	0.000000	0.500000	0.250000	0.0171 (18)	0.71 (15)
Si1	0.000000	0.000000	0.3834 (10)	0.011 (3)
Ca1	0.000000	0.000000	0.000000	0.011 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Fe1	0.0178 (19)	0.0178 (19)	0.016 (3)	0.000	0.000	0.000
Cu1	0.0178 (19)	0.0178 (19)	0.016 (3)	0.000	0.000	0.000
Si1	0.013 (4)	0.013 (4)	0.006 (7)	0.000	0.000	0.000
Ca1	0.009 (4)	0.009 (4)	0.013 (7)	0.000	0.000	0.000

Geometric parameters (Å, º) top

Fe1—Si1	2.422 (6)	Cu1—Si1ⁱ	2.422 (6)
Fe1—Si1ⁱ	2.422 (6)	Cu1—Si1ⁱⁱ	2.422 (6)
Fe1—Si1ⁱⁱ	2.422 (6)	Cu1—Si1ⁱⁱⁱ	2.422 (6)
Fe1—Si1ⁱⁱⁱ	2.422 (6)	Cu1—Ca1^vi	3.216 (2)
Fe1—Fe1ⁱ	2.857 (2)	Cu1—Ca1	3.216 (2)
Fe1—Fe1^iv	2.857 (2)	Cu1—Ca1ⁱⁱ	3.216 (2)
Fe1—Fe1ⁱⁱⁱ	2.857 (2)	Cu1—Ca1^vii	3.216 (2)
Fe1—Fe1^v	2.857 (2)	Si1—Si1^viii	2.33 (2)
Fe1—Ca1^vi	3.216 (2)	Si1—Ca1^vi	3.087 (4)
Fe1—Ca1	3.216 (2)	Si1—Ca1^ix	3.087 (4)
Fe1—Ca1ⁱⁱ	3.216 (2)	Si1—Ca1^x	3.087 (4)
Fe1—Ca1^vii	3.216 (2)	Si1—Ca1^vii	3.087 (4)
Cu1—Si1	2.422 (6)

Si1—Fe1—Si1ⁱ	107.7 (2)	Fe1ⁱ—Si1—Fe1	72.3 (2)
Si1—Fe1—Si1ⁱⁱ	113.1 (4)	Fe1^xi—Si1—Fe1	113.1 (4)
Si1ⁱ—Fe1—Si1ⁱⁱ	107.7 (2)	Si1^viii—Si1—Cu1	123.5 (2)
Si1—Fe1—Si1ⁱⁱⁱ	107.7 (2)	Si1^viii—Si1—Fe1ⁱⁱⁱ	123.5 (2)
Si1ⁱ—Fe1—Si1ⁱⁱⁱ	113.1 (4)	Fe1ⁱ—Si1—Fe1ⁱⁱⁱ	113.1 (4)
Si1ⁱⁱ—Fe1—Si1ⁱⁱⁱ	107.7 (2)	Fe1^xi—Si1—Fe1ⁱⁱⁱ	72.3 (2)
Si1—Fe1—Fe1ⁱ	53.85 (10)	Fe1—Si1—Fe1ⁱⁱⁱ	72.3 (2)
Si1ⁱ—Fe1—Fe1ⁱ	53.85 (10)	Si1^viii—Si1—Ca1^vi	67.78 (18)
Si1ⁱⁱ—Fe1—Fe1ⁱ	126.15 (10)	Fe1ⁱ—Si1—Ca1^vi	138.99 (9)
Si1ⁱⁱⁱ—Fe1—Fe1ⁱ	126.15 (10)	Fe1^xi—Si1—Ca1^vi	138.99 (9)
Si1—Fe1—Fe1^iv	126.15 (10)	Fe1—Si1—Ca1^vi	70.27 (4)
Si1ⁱ—Fe1—Fe1^iv	126.15 (10)	Cu1—Si1—Ca1^vi	70.27 (4)
Si1ⁱⁱ—Fe1—Fe1^iv	53.85 (10)	Fe1ⁱⁱⁱ—Si1—Ca1^vi	70.27 (4)
Si1ⁱⁱⁱ—Fe1—Fe1^iv	53.85 (10)	Si1^viii—Si1—Ca1^ix	67.78 (18)
Fe1ⁱ—Fe1—Fe1^iv	180.0	Fe1ⁱ—Si1—Ca1^ix	70.27 (4)
Si1—Fe1—Fe1ⁱⁱⁱ	53.85 (10)	Fe1^xi—Si1—Ca1^ix	70.27 (4)
Si1ⁱ—Fe1—Fe1ⁱⁱⁱ	126.15 (10)	Fe1—Si1—Ca1^ix	138.99 (9)
Si1ⁱⁱ—Fe1—Fe1ⁱⁱⁱ	126.15 (10)	Fe1ⁱⁱⁱ—Si1—Ca1^ix	138.99 (9)
Si1ⁱⁱⁱ—Fe1—Fe1ⁱⁱⁱ	53.85 (10)	Ca1^vi—Si1—Ca1^ix	135.6 (4)
Fe1ⁱ—Fe1—Fe1ⁱⁱⁱ	90.0	Si1^viii—Si1—Ca1^x	67.78 (18)
Fe1^iv—Fe1—Fe1ⁱⁱⁱ	90.0	Fe1ⁱ—Si1—Ca1^x	138.99 (9)
Si1—Fe1—Fe1^v	126.15 (10)	Fe1^xi—Si1—Ca1^x	70.27 (4)
Si1ⁱ—Fe1—Fe1^v	53.85 (10)	Fe1—Si1—Ca1^x	138.99 (9)
Si1ⁱⁱ—Fe1—Fe1^v	53.85 (10)	Fe1ⁱⁱⁱ—Si1—Ca1^x	70.27 (4)
Si1ⁱⁱⁱ—Fe1—Fe1^v	126.15 (10)	Ca1^vi—Si1—Ca1^x	81.78 (13)
Fe1ⁱ—Fe1—Fe1^v	90.0	Ca1^ix—Si1—Ca1^x	81.78 (13)
Fe1^iv—Fe1—Fe1^v	90.0	Si1^viii—Si1—Ca1^vii	67.78 (18)
Fe1ⁱⁱⁱ—Fe1—Fe1^v	180.0	Fe1ⁱ—Si1—Ca1^vii	70.27 (4)
Si1—Fe1—Ca1^vi	64.60 (15)	Fe1^xi—Si1—Ca1^vii	138.99 (9)
Si1ⁱ—Fe1—Ca1^vi	162.4 (2)	Fe1—Si1—Ca1^vii	70.27 (4)
Si1ⁱⁱ—Fe1—Ca1^vi	64.60 (15)	Fe1ⁱⁱⁱ—Si1—Ca1^vii	138.99 (9)
Si1ⁱⁱⁱ—Fe1—Ca1^vi	84.5 (2)	Ca1^vi—Si1—Ca1^vii	81.78 (13)
Fe1ⁱ—Fe1—Ca1^vi	116.37 (2)	Ca1^ix—Si1—Ca1^vii	81.78 (13)
Fe1^iv—Fe1—Ca1^vi	63.628 (19)	Ca1^x—Si1—Ca1^vii	135.6 (4)
Fe1ⁱⁱⁱ—Fe1—Ca1^vi	63.63 (2)	Si1ⁱⁱⁱ—Ca1—Si1^xii	180.0
Fe1^v—Fe1—Ca1^vi	116.37 (2)	Si1ⁱⁱⁱ—Ca1—Si1^xiii	135.6 (4)
Si1—Fe1—Ca1	84.5 (2)	Si1^xii—Ca1—Si1^xiii	44.4 (4)
Si1ⁱ—Fe1—Ca1	64.60 (15)	Si1ⁱⁱⁱ—Ca1—Si1^xiv	44.4 (4)
Si1ⁱⁱ—Fe1—Ca1	162.4 (2)	Si1^xii—Ca1—Si1^xiv	135.6 (4)
Si1ⁱⁱⁱ—Fe1—Ca1	64.60 (15)	Si1^xiii—Ca1—Si1^xiv	180.0
Fe1ⁱ—Fe1—Ca1	63.63 (2)	Si1ⁱⁱⁱ—Ca1—Si1ⁱ	81.78 (13)
Fe1^iv—Fe1—Ca1	116.37 (2)	Si1^xii—Ca1—Si1ⁱ	98.22 (13)
Fe1ⁱⁱⁱ—Fe1—Ca1	63.63 (2)	Si1^xiii—Ca1—Si1ⁱ	81.78 (13)
Fe1^v—Fe1—Ca1	116.37 (2)	Si1^xiv—Ca1—Si1ⁱ	98.22 (13)
Ca1^vi—Fe1—Ca1	127.26 (4)	Si1ⁱⁱⁱ—Ca1—Si1^xv	81.78 (13)
Si1—Fe1—Ca1ⁱⁱ	162.4 (2)	Si1^xii—Ca1—Si1^xv	98.22 (13)
Si1ⁱ—Fe1—Ca1ⁱⁱ	64.60 (15)	Si1^xiii—Ca1—Si1^xv	81.78 (13)
Si1ⁱⁱ—Fe1—Ca1ⁱⁱ	84.5 (2)	Si1^xiv—Ca1—Si1^xv	98.22 (13)
Si1ⁱⁱⁱ—Fe1—Ca1ⁱⁱ	64.60 (15)	Si1ⁱ—Ca1—Si1^xv	135.6 (4)
Fe1ⁱ—Fe1—Ca1ⁱⁱ	116.37 (2)	Si1ⁱⁱⁱ—Ca1—Si1^xvi	98.22 (13)
Fe1^iv—Fe1—Ca1ⁱⁱ	63.63 (2)	Si1^xii—Ca1—Si1^xvi	81.78 (13)
Fe1ⁱⁱⁱ—Fe1—Ca1ⁱⁱ	116.37 (2)	Si1^xiii—Ca1—Si1^xvi	98.22 (13)
Fe1^v—Fe1—Ca1ⁱⁱ	63.63 (2)	Si1^xiv—Ca1—Si1^xvi	81.78 (13)
Ca1^vi—Fe1—Ca1ⁱⁱ	127.26 (4)	Si1ⁱ—Ca1—Si1^xvi	44.4 (4)
Ca1—Fe1—Ca1ⁱⁱ	77.83 (7)	Si1^xv—Ca1—Si1^xvi	180.0
Si1—Fe1—Ca1^vii	64.60 (15)	Si1ⁱⁱⁱ—Ca1—Si1^xvii	98.22 (13)
Si1ⁱ—Fe1—Ca1^vii	84.5 (2)	Si1^xii—Ca1—Si1^xvii	81.78 (13)
Si1ⁱⁱ—Fe1—Ca1^vii	64.60 (15)	Si1^xiii—Ca1—Si1^xvii	98.22 (13)
Si1ⁱⁱⁱ—Fe1—Ca1^vii	162.4 (2)	Si1^xiv—Ca1—Si1^xvii	81.78 (13)
Fe1ⁱ—Fe1—Ca1^vii	63.63 (2)	Si1ⁱ—Ca1—Si1^xvii	180.0
Fe1^iv—Fe1—Ca1^vii	116.37 (2)	Si1^xv—Ca1—Si1^xvii	44.4 (4)
Fe1ⁱⁱⁱ—Fe1—Ca1^vii	116.37 (2)	Si1^xvi—Ca1—Si1^xvii	135.6 (4)
Fe1^v—Fe1—Ca1^vii	63.63 (2)	Si1ⁱⁱⁱ—Ca1—Fe1	45.14 (14)
Ca1^vi—Fe1—Ca1^vii	77.83 (7)	Si1^xii—Ca1—Fe1	134.86 (14)
Ca1—Fe1—Ca1^vii	127.26 (4)	Si1^xiii—Ca1—Fe1	96.72 (17)
Ca1ⁱⁱ—Fe1—Ca1^vii	127.26 (4)	Si1^xiv—Ca1—Fe1	83.28 (17)
Si1—Cu1—Si1ⁱ	107.7 (2)	Si1ⁱ—Ca1—Fe1	45.14 (14)
Si1—Cu1—Si1ⁱⁱ	113.1 (4)	Si1^xv—Ca1—Fe1	96.72 (17)
Si1ⁱ—Cu1—Si1ⁱⁱ	107.7 (2)	Si1^xvi—Ca1—Fe1	83.28 (17)
Si1—Cu1—Si1ⁱⁱⁱ	107.7 (2)	Si1^xvii—Ca1—Fe1	134.86 (14)
Si1ⁱ—Cu1—Si1ⁱⁱⁱ	113.1 (4)	Si1ⁱⁱⁱ—Ca1—Fe1ⁱⁱⁱ	45.14 (14)
Si1ⁱⁱ—Cu1—Si1ⁱⁱⁱ	107.7 (2)	Si1^xii—Ca1—Fe1ⁱⁱⁱ	134.86 (14)
Si1—Cu1—Ca1^vi	64.60 (15)	Si1^xiii—Ca1—Fe1ⁱⁱⁱ	96.72 (17)
Si1ⁱ—Cu1—Ca1^vi	162.4 (2)	Si1^xiv—Ca1—Fe1ⁱⁱⁱ	83.28 (17)
Si1ⁱⁱ—Cu1—Ca1^vi	64.60 (15)	Si1ⁱ—Ca1—Fe1ⁱⁱⁱ	96.72 (17)
Si1ⁱⁱⁱ—Cu1—Ca1^vi	84.5 (2)	Si1^xv—Ca1—Fe1ⁱⁱⁱ	45.14 (14)
Si1—Cu1—Ca1	84.5 (2)	Si1^xvi—Ca1—Fe1ⁱⁱⁱ	134.86 (14)
Si1ⁱ—Cu1—Ca1	64.60 (15)	Si1^xvii—Ca1—Fe1ⁱⁱⁱ	83.28 (17)
Si1ⁱⁱ—Cu1—Ca1	162.4 (2)	Fe1—Ca1—Fe1ⁱⁱⁱ	52.74 (4)
Si1ⁱⁱⁱ—Cu1—Ca1	64.60 (15)	Si1ⁱⁱⁱ—Ca1—Cu1	45.14 (14)
Ca1^vi—Cu1—Ca1	127.26 (4)	Si1^xii—Ca1—Cu1	134.86 (14)
Si1—Cu1—Ca1ⁱⁱ	162.4 (2)	Si1^xiii—Ca1—Cu1	96.72 (17)
Si1ⁱ—Cu1—Ca1ⁱⁱ	64.60 (15)	Si1^xiv—Ca1—Cu1	83.28 (17)
Si1ⁱⁱ—Cu1—Ca1ⁱⁱ	84.5 (2)	Si1ⁱ—Ca1—Cu1	45.14 (14)
Si1ⁱⁱⁱ—Cu1—Ca1ⁱⁱ	64.60 (15)	Si1^xv—Ca1—Cu1	96.72 (17)
Ca1^vi—Cu1—Ca1ⁱⁱ	127.26 (4)	Si1^xvi—Ca1—Cu1	83.28 (17)
Ca1—Cu1—Ca1ⁱⁱ	77.83 (7)	Si1^xvii—Ca1—Cu1	134.86 (14)
Si1—Cu1—Ca1^vii	64.60 (15)	Si1ⁱⁱⁱ—Ca1—Fe1^xviii	134.86 (14)
Si1ⁱ—Cu1—Ca1^vii	84.5 (2)	Si1^xii—Ca1—Fe1^xviii	45.14 (14)
Si1ⁱⁱ—Cu1—Ca1^vii	64.60 (15)	Si1^xiii—Ca1—Fe1^xviii	83.28 (17)
Si1ⁱⁱⁱ—Cu1—Ca1^vii	162.4 (2)	Si1^xiv—Ca1—Fe1^xviii	96.72 (17)
Ca1^vi—Cu1—Ca1^vii	77.83 (7)	Si1ⁱ—Ca1—Fe1^xviii	134.86 (14)
Ca1—Cu1—Ca1^vii	127.26 (4)	Si1^xv—Ca1—Fe1^xviii	83.28 (17)
Ca1ⁱⁱ—Cu1—Ca1^vii	127.26 (4)	Si1^xvi—Ca1—Fe1^xviii	96.72 (17)
Si1^viii—Si1—Fe1ⁱ	123.5 (2)	Si1^xvii—Ca1—Fe1^xviii	45.14 (14)
Si1^viii—Si1—Fe1^xi	123.5 (2)	Fe1—Ca1—Fe1^xviii	180.0
Fe1ⁱ—Si1—Fe1^xi	72.3 (2)	Fe1ⁱⁱⁱ—Ca1—Fe1^xviii	127.26 (4)
Si1^viii—Si1—Fe1	123.5 (2)

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

Funding information

Funding for this research was provided by: The National Natural Science Foundation of China (grant No. 52173231; grant No. 51925105); Hebei Natural Science Foundation (grant No. E2022203182); The Innovation Ability Promotion Project of Hebei supported by Hebei Key Lab for Optimizing Metal Product Technology and Performance (grant No. 22567609H); Slovak national agencies (grant Nos. VEGA 2/0144/21, APVV19-0369, 87 APVV-20-0124).

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