Structural analysis of perovskite LaCr1 − xNixO3 by Rietveld refinement of X-ray powder diffraction data

Yang, J.

doi:10.1107/S0108768108005739

Structural analysis of perovskite LaCr_1 − xNi_xO₃ by Rietveld refinement of X-ray powder diffraction data

The crystal structure of perovskite LaCr_1 − xNi_xO₃ (0 ≤ x ≤ 1.0) has been systematically investigated by analyzing X-ray powder-diffraction data taken at room temperature. Rietveld refinement has confirmed the structural evolution from the orthorhombic phase (Pbnm, Z = 4) to the two-phase (the orthorhombic and the rhombohedral phases) region around x = 0.7, then to the rhombohedral ( $R\bar 3c$ , Z = 2) phase for 0.8 ≤ x ≤ 1.0. The lattice parameters are also obtained in the refinement process. The results are discussed in terms of reduced Cr/Ni—O bond length with increasing Ni-doping level, leading to an increased tolerance factor caused by the substitution of smaller Ni³⁺ ( $R_{\rm Ni^{3 + } }$ = 0.60 Å, six-coordinate) ions for larger Cr³⁺ ( $R_{\rm Cr^{3 + } }$ = 0.615 Å, six-coordinate) ions.

Keywords: ceramics; perovskite; X-ray powder diffraction.

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Supporting information

	Crystallographic Information File (CIF) https://doi.org/10.1107/S0108768108005739/bp5009sup1.cif Contains datablocks global, LaCrO3, Cr2O3, LaCr0.7Ni0.3O3, LaCr0.4Ni0.6O3, LaCr0.3Ni0.7O3_Pbnm, LaCr0.3Ni0.7O3_R-3c, LaCr0.2Ni0.8O3, LaCr0.1Ni0.9O3, LaNiO3
	Rietveld powder data file (CIF format) https://doi.org/10.1107/S0108768108005739/bp5009LaCrO3sup2.rtv Contains datablock LaCrO3
	Rietveld powder data file (CIF format) https://doi.org/10.1107/S0108768108005739/bp5009LaCr0.7Ni0.3O3sup3.rtv Contains datablock LaCr0.7Ni0.3O3
	Rietveld powder data file (CIF format) https://doi.org/10.1107/S0108768108005739/bp5009LaCr0.4Ni0.6O3sup4.rtv Contains datablock LaCr0.4Ni0.6O3
	Rietveld powder data file (CIF format) https://doi.org/10.1107/S0108768108005739/bp5009LaCr0.3Ni0.7O3sup5.rtv Contains datablock LaCr0.3Ni0.7O3
	Rietveld powder data file (CIF format) https://doi.org/10.1107/S0108768108005739/bp5009LaCr0.2Ni0.8O3sup6.rtv Contains datablock LaCr0.2Ni0.8O3
	Rietveld powder data file (CIF format) https://doi.org/10.1107/S0108768108005739/bp5009LaCr0.1Ni0.9O3sup7.rtv Contains datablock LaCr0.1Ni0.9O3
	Rietveld powder data file (CIF format) https://doi.org/10.1107/S0108768108005739/bp5009LaNiO3sup8.rtv Contains datablock LaNiO3

Computing details top

Data collection: X'Pert PRO MPD (Philips, 2003) for LaCrO3; X'Pert PRO MPD(Philips, 2003) for Cr2O3, LaCr0.7Ni0.3O3, LaCr0.4Ni0.6O3, LaCr0.3Ni0.7O3_Pbnm, LaCr0.3Ni0.7O3_R-3c, LaCr0.2Ni0.8O3, LaCr0.1Ni0.9O3, LaNiO3. Cell refinement: X'Pert PRO MPD (Philips, 2003) for LaCrO3; X'Pert PRO MPD(Philips, 2003) for Cr2O3, LaCr0.7Ni0.3O3, LaCr0.4Ni0.6O3, LaCr0.3Ni0.7O3_Pbnm, LaCr0.3Ni0.7O3_R-3c, LaCr0.2Ni0.8O3, LaCr0.1Ni0.9O3, LaNiO3. Data reduction: X'Pert PRO MPD (Philips, 2003) for LaCrO3; X'Pert PRO MPD(Philips, 2003) for Cr2O3, LaCr0.7Ni0.3O3, LaCr0.4Ni0.6O3, LaCr0.3Ni0.7O3_Pbnm, LaCr0.3Ni0.7O3_R-3c, LaCr0.2Ni0.8O3, LaCr0.1Ni0.9O3, LaNiO3. For all compounds, program(s) used to solve structure: Rietica (Hunter, 1997); program(s) used to refine structure: Rietica (Hunter, 1997); molecular graphics: Rietica (Hunter, 1997).

Figures top

(LaCrO3) top

Crystal data top

CrLaO₃	Z = 4
M_r = 238.90	D_x = 6.773 Mg m⁻³
Orthorhombic, Pbnm	Cu Kα radiation, λ = 1.54176 Å
a = 5.5133 (1) Å	T = 298 K
b = 5.4759 (6) Å	green
c = 7.7585 (9) Å	cylinder, 0.07 × 0.06 mm
V = 234.24 (1) Å³

Data collection top

Philips X'Pert PRO diffractometer	Data collection mode: reflection
Radiation source: Philips high intensity ceramic sealed tube	Scan method: step
Graphite monochromator	2θ_min = 20°, 2θ_max = 80°, 2θ_step = 0.017°
Specimen mounting: flat plate

Refinement top

R_p = 0.090	31 parameters
R_wp = 0.122	0 restraints
R_exp = ?	0 constraints
R_Bragg = 0.015	Weighting scheme based on measured s.u.'s w = 1/[σ²(F) + 0.0001F²]
χ² = 0.000	(Δ/σ)_max = 0.0001
3583 data points

Crystal data top

CrLaO₃	V = 234.24 (1) Å³
M_r = 238.90	Z = 4
Orthorhombic, Pbnm	Cu Kα radiation, λ = 1.54176 Å
a = 5.5133 (1) Å	T = 298 K
b = 5.4759 (6) Å	cylinder, 0.07 × 0.06 mm
c = 7.7585 (9) Å

Data collection top

Philips X'Pert PRO diffractometer	Scan method: step
Specimen mounting: flat plate	2θ_min = 20°, 2θ_max = 80°, 2θ_step = 0.017°
Data collection mode: reflection

Refinement top

R_p = 0.090	χ² = 0.000
R_wp = 0.122	3583 data points
R_exp = ?	31 parameters
R_Bragg = 0.015	0 restraints

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

	x	y	z	U_iso*/U_eq
La	0.4971 (5)	0.0180 (7)	0.25	0.6*
Cr	0	0	0	0.6*
O1	0.5594 (3)	0.4993 (6)	0.25	0.6*
O2	0.2249 (1)	0.2688 (2)	0.0376 (7)	0.6*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
?	?	?	?	?	?	?

Geometric parameters (Å, º) top

Cr—O1	4.555 (2)	Cr—O2	1.9466 (12)

Cr—O1—Cr	160.82	Cr—O2—Cr	160.23

(Cr2O3) top

Crystal data top

Cr₂O₃	Z = 2
M_r = 151.99	D_x = 5.235 Mg m⁻³
Hexagonal, R3c	Cu Kα radiation, λ = 1.54176 Å
a = 4.958 (1) Å	T = 298 K
c = 13.59 (3) Å	green
V = 289.3 (6) Å³	cylinder, 0.07 × 0.06 mm

Data collection top

Philips X'Pert PRO diffractometer	Data collection mode: reflection
Radiation source: Philips high intensity ceramic sealed tube	Scan method: step
Graphite monochromator	2θ_min = 20°, 2θ_max = 80°, 2θ_step = 0.017°
Specimen mounting: flat plate

Refinement top

Least-squares matrix: full	3583 data points
R_p = 0.090	31 parameters
R_wp = 0.122	0 restraints
R_exp = ?	0 constraints
R_Bragg = 0.015	Weighting scheme based on measured s.u.'s w = 1/[σ²(F) + 0.0001F²]
χ² = 0.000	(Δ/σ)_max = 0.0001

Crystal data top

Cr₂O₃	V = 289.3 (6) Å³
M_r = 151.99	Z = 2
Hexagonal, R3c	Cu Kα radiation, λ = 1.54176 Å
a = 4.958 (1) Å	T = 298 K
c = 13.59 (3) Å	cylinder, 0.07 × 0.06 mm

Data collection top

Philips X'Pert PRO diffractometer	Scan method: step
Specimen mounting: flat plate	2θ_min = 20°, 2θ_max = 80°, 2θ_step = 0.017°
Data collection mode: reflection

Refinement top

R_p = 0.090	χ² = 0.000
R_wp = 0.122	3583 data points
R_exp = ?	31 parameters
R_Bragg = 0.015	0 restraints

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

	x	y	z	U_iso*/U_eq
Cr	0	0	0.3518 (3)	0.6*
O	0.3194 (8)	0	0.25	0.6*

Geometric parameters (Å, º) top

CR—O	2.103 (6)

Cr—O—Cr	170.30

(LaCr0.7Ni0.3O3) top

Crystal data top

Cr_0.7LaNi_0.3O₃	Z = 4
M_r = 240.91	D_x = 6.855 Mg m⁻³
Orthorhombic, Pbnm	Cu Kα radiation, λ = 1.54176 Å
a = 5.5094 (9) Å	T = 298 K
b = 5.4740 (1) Å	grey-green
c = 7.7536 (8) Å	cylinder, 0.07 × 0.06 mm
V = 233.84 (1) Å³

Data collection top

Philips X'Pert PRO diffractometer	Data collection mode: reflection
Radiation source: Philips high intensity ceramic sealed tube	Scan method: step
Graphite monochromator	2θ_min = 20°, 2θ_max = 80°, 2θ_step = 0.017°
Specimen mounting: flat plate

Refinement top

Least-squares matrix: full	3583 data points
R_p = 0.079	28 parameters
R_wp = 0.100	0 restraints
R_exp = ?	0 constraints
R_Bragg = 0.023	Weighting scheme based on measured s.u.'s w = 1/[σ²(F) + 0.0001F²]
χ² = 0.000	(Δ/σ)_max = 0.0001

Crystal data top

Cr_0.7LaNi_0.3O₃	V = 233.84 (1) Å³
M_r = 240.91	Z = 4
Orthorhombic, Pbnm	Cu Kα radiation, λ = 1.54176 Å
a = 5.5094 (9) Å	T = 298 K
b = 5.4740 (1) Å	cylinder, 0.07 × 0.06 mm
c = 7.7536 (8) Å

Data collection top

Philips X'Pert PRO diffractometer	Scan method: step
Specimen mounting: flat plate	2θ_min = 20°, 2θ_max = 80°, 2θ_step = 0.017°
Data collection mode: reflection

Refinement top

R_p = 0.079	χ² = 0.000
R_wp = 0.100	3583 data points
R_exp = ?	28 parameters
R_Bragg = 0.023	0 restraints

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

	x	y	z	U_iso*/U_eq	Occ. (<1)
Cr	0	0	0	0.6*	0.7
La	0.4979 (8)	0.0203 (8)	0.25	0.6*
Ni	0	0	0	0.6*	0.3
O1	0.5744 (6)	0.4956 (1)	0.25	0.6*
O2	0.2324 (4)	0.3082 (1)	0.0236 (7)	0.6*

(LaCr0.4Ni0.6O3) top

Crystal data top

Cr_0.4LaNi_0.6O₃	Z = 4
M_r = 242.92	D_x = 6.855 Mg m⁻³
Orthorhombic, Pbnm	Cu Kα radiation, λ = 1.54176 Å
a = 5.5180 (1) Å	T = 298 K
b = 5.4735 (3) Å	grey-green
c = 7.7529 (5) Å	cylinder, 0.07 × 0.06 mm
V = 234.16 (1) Å³

Data collection top

Philips X'Pert PRO diffractometer	Data collection mode: reflection
Radiation source: Philips high intensity ceramic sealed tube	Scan method: step
Graphite monochromator	2θ_min = 20°, 2θ_max = 80°, 2θ_step = 0.017°
Specimen mounting: flat plate

Refinement top

Least-squares matrix: full	3583 data points
R_p = 0.067	23 parameters
R_wp = 0.086	0 restraints
R_exp = ?	0 constraints
R_Bragg = 0.017	Weighting scheme based on measured s.u.'s w = 1/[σ²(F) + 0.0001F²]
χ² = 0.000	(Δ/σ)_max = 0.0001

Crystal data top

Cr_0.4LaNi_0.6O₃	V = 234.16 (1) Å³
M_r = 242.92	Z = 4
Orthorhombic, Pbnm	Cu Kα radiation, λ = 1.54176 Å
a = 5.5180 (1) Å	T = 298 K
b = 5.4735 (3) Å	cylinder, 0.07 × 0.06 mm
c = 7.7529 (5) Å

Data collection top

Philips X'Pert PRO diffractometer	Scan method: step
Specimen mounting: flat plate	2θ_min = 20°, 2θ_max = 80°, 2θ_step = 0.017°
Data collection mode: reflection

Refinement top

R_p = 0.067	χ² = 0.000
R_wp = 0.086	3583 data points
R_exp = ?	23 parameters
R_Bragg = 0.017	0 restraints

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

	x	y	z	U_iso*/U_eq	Occ. (<1)
La	0.4926 (4)	0.0242 (1)	0.25	0.6*
Cr	0	0	0	0.6*	0.4
Ni	0	0	0	0.6*	0.6
O1	0.5656 (2)	0.4865 (4)	0.25	0.6*
O2	0.2327 (1)	0.2863 (3)	0.0286 (8)	0.6*

(LaCr0.3Ni0.7O3_Pbnm) top

Crystal data top

Cr_0.3LaNi_0.7O₃	Z = 4
M_r = 243.59	D_x = 6.954 Mg m⁻³
Orthorhombic, Pbnm	Cu Kα radiation, λ = 1.54176 Å
a = 5.5032 (2) Å	T = 298 K
b = 5.4612 (6) Å	grey-green
c = 7.7407 (7) Å	cylinder, 0.07 × 0.06 mm
V = 232.64 (1) Å³

Data collection top

Philips X'Pert PRO diffractometer	Data collection mode: reflection
Radiation source: Philips high intensity ceramic sealed tube	Scan method: step
Graphite monochromator	2θ_min = 20°, 2θ_max = 80°, 2θ_step = 0.017°
Specimen mounting: flat plate

Refinement top

Least-squares matrix: full	3583 data points
R_p = 0.087	25 parameters
R_wp = 0.117	0 restraints
R_exp = ?	0 constraints
R_Bragg = 0.051	Weighting scheme based on measured s.u.'s w = 1/[σ²(F) + 0.0001F²]
χ² = 0.001	(Δ/σ)_max = 0.0001

Crystal data top

Cr_0.3LaNi_0.7O₃	V = 232.64 (1) Å³
M_r = 243.59	Z = 4
Orthorhombic, Pbnm	Cu Kα radiation, λ = 1.54176 Å
a = 5.5032 (2) Å	T = 298 K
b = 5.4612 (6) Å	cylinder, 0.07 × 0.06 mm
c = 7.7407 (7) Å

Data collection top

Philips X'Pert PRO diffractometer	Scan method: step
Specimen mounting: flat plate	2θ_min = 20°, 2θ_max = 80°, 2θ_step = 0.017°
Data collection mode: reflection

Refinement top

R_p = 0.087	χ² = 0.001
R_wp = 0.117	3583 data points
R_exp = ?	25 parameters
R_Bragg = 0.051	0 restraints

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

	x	y	z	U_iso*/U_eq	Occ. (<1)
La	0.4983 (5)	0.0206 (9)	0.25	0.6*
Cr	0	0	0	0.6*	0.3
Ni	0	0	0	0.6*	0.7
O1	0.5791 (3)	0.5009 (5)	0.25	0.6*
O2	0.2480 (3)	0.3032 (1)	0.0201 (4)	0.6*

(LaCr0.3Ni0.7O3_R-3c) top

Crystal data top

Cr_0.3LaNi_0.7O₃	Z = 2
M_r = 243.59	D_x = 7.056 Mg m⁻³
Hexagonal, R3c	Cu Kα radiation, λ = 1.54176 Å
a = 5.4831 (2) Å	T = 298 K
c = 13.2091 (3) Å	grey-green
V = 343.92 (1) Å³	cylinder, 0.07 × 0.06 mm

Data collection top

Philips X'Pert PRO diffractometer	Data collection mode: reflection
Radiation source: Philips high intensity ceramic sealed tube	Scan method: step
Graphite monochromator	2θ_min = 20°, 2θ_max = 80°, 2θ_step = 0.017°
Specimen mounting: flat plate

Refinement top

Least-squares matrix: full	3583 data points
R_p = 0.087	25 parameters
R_wp = 0.117	0 restraints
R_exp = ?	0 constraints
R_Bragg = 0.051	Weighting scheme based on measured s.u.'s w = 1/[σ²(F) + 0.0001F²]
χ² = 0.001	(Δ/σ)_max = 0.0001

Crystal data top

Cr_0.3LaNi_0.7O₃	V = 343.92 (1) Å³
M_r = 243.59	Z = 2
Hexagonal, R3c	Cu Kα radiation, λ = 1.54176 Å
a = 5.4831 (2) Å	T = 298 K
c = 13.2091 (3) Å	cylinder, 0.07 × 0.06 mm

Data collection top

Philips X'Pert PRO diffractometer	Scan method: step
Specimen mounting: flat plate	2θ_min = 20°, 2θ_max = 80°, 2θ_step = 0.017°
Data collection mode: reflection

Refinement top

R_p = 0.087	χ² = 0.001
R_wp = 0.117	3583 data points
R_exp = ?	25 parameters
R_Bragg = 0.051	0 restraints

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

	x	y	z	U_iso*/U_eq	Occ. (<1)
La	0	0	0.25	0.6*
Cr	0	0	0	0.6*	0.3
Ni	0	0	0	0.6*	0.7
O	0.5523 (3)	0	0.25	0.6*

(LaCr0.2Ni0.8O3) top

Crystal data top

Cr_0.2LaNi_0.8O₃	Z = 2
M_r = 244.26	D_x = 7.082 Mg m⁻³
Hexagonal, R3c	Cu Kα radiation, λ = 1.54176 Å
a = 5.4809 (3) Å	T = 298 K
c = 13.2070 (5) Å	grey-green
V = 343.59 (1) Å³	cylinder, 0.07 × 0.06 mm

Data collection top

Philips X'Pert PRO diffractometer	Data collection mode: reflection
Radiation source: Philips high intensity ceramic sealed tube	Scan method: step
Graphite monochromator	2θ_min = 20°, 2θ_max = 80°, 2θ_step = 0.017°
Specimen mounting: flat plate

Refinement top

Least-squares matrix: full	3583 data points
R_p = 0.072	25 parameters
R_wp = 0.093	0 restraints
R_exp = ?	0 constraints
R_Bragg = 0.033	Weighting scheme based on measured s.u.'s w = 1/[σ²(F) + 0.0001F²]
χ² = 0.000	(Δ/σ)_max = 0.0001

Crystal data top

Cr_0.2LaNi_0.8O₃	V = 343.59 (1) Å³
M_r = 244.26	Z = 2
Hexagonal, R3c	Cu Kα radiation, λ = 1.54176 Å
a = 5.4809 (3) Å	T = 298 K
c = 13.2070 (5) Å	cylinder, 0.07 × 0.06 mm

Data collection top

Philips X'Pert PRO diffractometer	Scan method: step
Specimen mounting: flat plate	2θ_min = 20°, 2θ_max = 80°, 2θ_step = 0.017°
Data collection mode: reflection

Refinement top

R_p = 0.072	χ² = 0.000
R_wp = 0.093	3583 data points
R_exp = ?	25 parameters
R_Bragg = 0.033	0 restraints

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

	x	y	z	U_iso*/U_eq	Occ. (<1)
La	0	0	0.25	0.6*
Cr	0	0	0	0.6*	0.2
Ni	0	0	0	0.6*	0.8
O	0.5517 (4)	0	0.25	0.6*

(LaCr0.1Ni0.9O3) top

Crystal data top

Cr_0.1LaNi_0.9O₃	Z = 2
M_r = 244.93	D_x = 7.122 Mg m⁻³
Hexagonal, R3c	Cu Kα radiation, λ = 1.54176 Å
a = 5.4747 (6) Å	T = 298 K
c = 13.1990 (3) Å	grey
V = 342.60 (2) Å³	cylinder, 0.07 × 0.06 mm

Data collection top

Philips X'Pert PRO diffractometer	Data collection mode: reflection
Radiation source: Philips high intensity ceramic sealed tube	Scan method: step
Graphite monochromator	2θ_min = 20°, 2θ_max = 80°, 2θ_step = 0.017°
Specimen mounting: flat plate

Refinement top

Least-squares matrix: full	3583 data points
R_p = 0.095	25 parameters
R_wp = 0.116	0 restraints
R_exp = ?	0 constraints
R_Bragg = 0.089	Weighting scheme based on measured s.u.'s w = 1/[σ²(F) + 0.0001F²]
χ² = 0.000	(Δ/σ)_max = 0.0001

Crystal data top

Cr_0.1LaNi_0.9O₃	V = 342.60 (2) Å³
M_r = 244.93	Z = 2
Hexagonal, R3c	Cu Kα radiation, λ = 1.54176 Å
a = 5.4747 (6) Å	T = 298 K
c = 13.1990 (3) Å	cylinder, 0.07 × 0.06 mm

Data collection top

Philips X'Pert PRO diffractometer	Scan method: step
Specimen mounting: flat plate	2θ_min = 20°, 2θ_max = 80°, 2θ_step = 0.017°
Data collection mode: reflection

Refinement top

R_p = 0.095	χ² = 0.000
R_wp = 0.116	3583 data points
R_exp = ?	25 parameters
R_Bragg = 0.089	0 restraints

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

	x	y	z	U_iso*/U_eq	Occ. (<1)
La	0	0	0.25	0.6*
Cr	0	0	0	0.6*	0.1
Ni	0	0	0	0.6*	0.9
O	0.5507 (3)	0	0.25	0.6*

(LaNiO3) top

Crystal data top

LaNiO₃	Z = 2
M_r = 245.60	D_x = 7.221 Mg m⁻³
Hexagonal, R3c	Cu Kα radiation, λ = 1.54176 Å
a = 5.4561 (1) Å	T = 298 K
c = 13.1432 (3) Å	grey
V = 338.84 (1) Å³	cylinder, 0.07 × 0.06 mm

Data collection top

Philips X'Pert PRO diffractometer	Data collection mode: reflection
Radiation source: Philips high intensity ceramic sealed tube	Scan method: step
Graphite monochromator	2θ_min = 20°, 2θ_max = 80°, 2θ_step = 0.017°
Specimen mounting: flat plate

Refinement top

Least-squares matrix: full	3583 data points
R_p = 0.106	18 parameters
R_wp = 0.124	0 restraints
R_exp = ?	0 constraints
R_Bragg = 0.072	Weighting scheme based on measured s.u.'s w = 1/[σ²(F) + 0.0001F²]
χ² = 0.000	(Δ/σ)_max = 0.0001

Crystal data top

LaNiO₃	V = 338.84 (1) Å³
M_r = 245.60	Z = 2
Hexagonal, R3c	Cu Kα radiation, λ = 1.54176 Å
a = 5.4561 (1) Å	T = 298 K
c = 13.1432 (3) Å	cylinder, 0.07 × 0.06 mm

Data collection top

Philips X'Pert PRO diffractometer	Scan method: step
Specimen mounting: flat plate	2θ_min = 20°, 2θ_max = 80°, 2θ_step = 0.017°
Data collection mode: reflection

Refinement top

R_p = 0.106	χ² = 0.000
R_wp = 0.124	3583 data points
R_exp = ?	18 parameters
R_Bragg = 0.072	0 restraints

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

	x	y	z	U_iso*/U_eq
La	0	0	0.25	0.6*
Ni	0	0	0	0.6*
O	0.5501 (2)	0	0.25	0.6*

Experimental details

	(LaCrO3)	(Cr2O3)	(LaCr0.7Ni0.3O3)	(LaCr0.4Ni0.6O3)
Crystal data
Chemical formula	CrLaO₃	Cr₂O₃	Cr_0.7LaNi_0.3O₃	Cr_0.4LaNi_0.6O₃
M_r	238.90	151.99	240.91	242.92
Crystal system, space group	Orthorhombic, Pbnm	Hexagonal, R3c	Orthorhombic, Pbnm	Orthorhombic, Pbnm
Temperature (K)	298	298	298	298
a, b, c (Å)	5.5133 (1), 5.4759 (6), 7.7585 (9)	4.958 (1), 4.958 (1), 13.59 (3)	5.5094 (9), 5.4740 (1), 7.7536 (8)	5.5180 (1), 5.4735 (3), 7.7529 (5)
α, β, γ (°)	90, 90, 90	90, 90, 120	90, 90, 90	90, 90, 90
V (Å³)	234.24 (1)	289.3 (6)	233.84 (1)	234.16 (1)
Z	4	2	4	4
Radiation type	Cu Kα, λ = 1.54176 Å	Cu Kα, λ = 1.54176 Å	Cu Kα, λ = 1.54176 Å	Cu Kα, λ = 1.54176 Å
Specimen shape, size (mm)	Cylinder, 0.07 × 0.06	Cylinder, 0.07 × 0.06	Cylinder, 0.07 × 0.06	Cylinder, 0.07 × 0.06

Data collection
Diffractometer	Philips X'Pert PRO diffractometer	Philips X'Pert PRO diffractometer	Philips X'Pert PRO diffractometer	Philips X'Pert PRO diffractometer
Specimen mounting	Flat plate	Flat plate	Flat plate	Flat plate
Data collection mode	Reflection	Reflection	Reflection	Reflection
Scan method	Step	Step	Step	Step
2θ values (°)	2θ_min = 20 2θ_max = 80 2θ_step = 0.017	2θ_min = 20 2θ_max = 80 2θ_step = 0.017	2θ_min = 20 2θ_max = 80 2θ_step = 0.017	2θ_min = 20 2θ_max = 80 2θ_step = 0.017

Refinement
R factors and goodness of fit	R_p = 0.090, R_wp = 0.122, R_exp = ?, R_Bragg = 0.015, χ² = 0.000	R_p = 0.090, R_wp = 0.122, R_exp = ?, R_Bragg = 0.015, χ² = 0.000	R_p = 0.079, R_wp = 0.100, R_exp = ?, R_Bragg = 0.023, χ² = 0.000	R_p = 0.067, R_wp = 0.086, R_exp = ?, R_Bragg = 0.017, χ² = 0.000
No. of data points	3583	3583	3583	3583
No. of parameters	31	31	28	23

	(LaCr0.3Ni0.7O3_Pbnm)	(LaCr0.3Ni0.7O3_R-3c)	(LaCr0.2Ni0.8O3)	(LaCr0.1Ni0.9O3)
Crystal data
Chemical formula	Cr_0.3LaNi_0.7O₃	Cr_0.3LaNi_0.7O₃	Cr_0.2LaNi_0.8O₃	Cr_0.1LaNi_0.9O₃
M_r	243.59	243.59	244.26	244.93
Crystal system, space group	Orthorhombic, Pbnm	Hexagonal, R3c	Hexagonal, R3c	Hexagonal, R3c
Temperature (K)	298	298	298	298
a, b, c (Å)	5.5032 (2), 5.4612 (6), 7.7407 (7)	5.4831 (2), 5.4831 (2), 13.2091 (3)	5.4809 (3), 5.4809 (3), 13.2070 (5)	5.4747 (6), 5.4747 (6), 13.1990 (3)
α, β, γ (°)	90, 90, 90	90, 90, 120	90, 90, 120	90, 90, 120
V (Å³)	232.64 (1)	343.92 (1)	343.59 (1)	342.60 (2)
Z	4	2	2	2
Radiation type	Cu Kα, λ = 1.54176 Å	Cu Kα, λ = 1.54176 Å	Cu Kα, λ = 1.54176 Å	Cu Kα, λ = 1.54176 Å
Specimen shape, size (mm)	Cylinder, 0.07 × 0.06	Cylinder, 0.07 × 0.06	Cylinder, 0.07 × 0.06	Cylinder, 0.07 × 0.06

Data collection
Diffractometer	Philips X'Pert PRO diffractometer	Philips X'Pert PRO diffractometer	Philips X'Pert PRO diffractometer	Philips X'Pert PRO diffractometer
Specimen mounting	Flat plate	Flat plate	Flat plate	Flat plate
Data collection mode	Reflection	Reflection	Reflection	Reflection
Scan method	Step	Step	Step	Step
2θ values (°)	2θ_min = 20 2θ_max = 80 2θ_step = 0.017	2θ_min = 20 2θ_max = 80 2θ_step = 0.017	2θ_min = 20 2θ_max = 80 2θ_step = 0.017	2θ_min = 20 2θ_max = 80 2θ_step = 0.017

Refinement
R factors and goodness of fit	R_p = 0.087, R_wp = 0.117, R_exp = ?, R_Bragg = 0.051, χ² = 0.001	R_p = 0.087, R_wp = 0.117, R_exp = ?, R_Bragg = 0.051, χ² = 0.001	R_p = 0.072, R_wp = 0.093, R_exp = ?, R_Bragg = 0.033, χ² = 0.000	R_p = 0.095, R_wp = 0.116, R_exp = ?, R_Bragg = 0.089, χ² = 0.000
No. of data points	3583	3583	3583	3583
No. of parameters	25	25	25	25

	(LaNiO3)
Crystal data
Chemical formula	LaNiO₃
M_r	245.60
Crystal system, space group	Hexagonal, R3c
Temperature (K)	298
a, b, c (Å)	5.4561 (1), 5.4561 (1), 13.1432 (3)
α, β, γ (°)	90, 90, 120
V (Å³)	338.84 (1)
Z	2
Radiation type	Cu Kα, λ = 1.54176 Å
Specimen shape, size (mm)	Cylinder, 0.07 × 0.06

Data collection
Diffractometer	Philips X'Pert PRO diffractometer
Specimen mounting	Flat plate
Data collection mode	Reflection
Scan method	Step
2θ values (°)	2θ_min = 20 2θ_max = 80 2θ_step = 0.017

Refinement
R factors and goodness of fit	R_p = 0.106, R_wp = 0.124, R_exp = ?, R_Bragg = 0.072, χ² = 0.000
No. of data points	3583
No. of parameters	18

Computer programs: X'Pert PRO MPD (Philips, 2003), X'Pert PRO MPD(Philips, 2003), Rietica (Hunter, 1997).

Format		BIBTeX
		EndNote
		RefMan
		Refer
		Medline
		CIF
		SGML
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Format		BIBTeX
		EndNote
		RefMan
		Refer
		Medline
		CIF
		SGML
		Text
		Plain Text