Redetermination of Sr2PdO3 from single-crystal X-ray data

Thakur, G.S.; Reuter, H.; Felser, C.; Jansen, M.

doi:10.1107/S2056989018017176

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Volume 75| Part 1| January 2019| Pages 30-32

https://doi.org/10.1107/S2056989018017176

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Redetermination of Sr₂PdO₃ from single-crystal X-ray data

Gohil S. Thakur,^a ^* Hans Reuter,^b Claudia Felser ^a and Martin Jansen ^a,^c

^aMax Planck Institut for Chemical Physics of Solids, Nöthnitzer Straβe 40, 01187, Dresden, Germany, ^bInstitute for Chemistry of New Materials, University of Osnabrück, Barbarastrasse, 7, 49076 Osnabrück, Germany, and ^cMax Planck Institut for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart, Germany
^*Correspondence e-mail: gohil.thakur@cpfs.mpg.de

Edited by M. Weil, Vienna University of Technology, Austria (Received 9 November 2018; accepted 3 December 2018; online 1 January 2019)

The crystal structure redetermination of Sr₂PdO₃ (distrontium palladium trioxide) was carried out using high-quality single-crystal X-ray data. The Sr₂PdO₃ structure has been described previously in at least three reports [Wasel-Nielen & Hoppe (1970 ). Z. Anorg. Allg. Chem. 375, 209–213; Muller & Roy (1971 ). Adv. Chem. Ser. 98, 28–38; Nagata et al. (2002 ). J. Alloys Compd. 346, 50–56], all based on powder X-ray diffraction data. The current structure refinement of Sr₂PdO₃, as compared to previous powder data refinements, leads to more precise cell parameters and fractional coordinates, together with anisotropic displacement parameters for all sites. The compound is confirmed to have the orthorhombic Sr₂CuO₃ structure type (space group Immm) as reported previously. The structure consists of infinite chains of corner-sharing PdO₄ plaquettes interspersed by Sr^II atoms. A brief comparison of Sr₂PdO₃ with the related K₂NiF₄ structure type is given.

Keywords: crystal structure; K₂NiF₄ structure; Sr₂CuO₃ structure type; linear chain compound.

CCDC reference: 1882781

1. Chemical context

Low-dimensional transition-metal oxides with chain structures have received attention since they can enable interesting physical phenomena such as spin 1/2 antiferromagnetic Heisenberg coupling (Motoyama et al., 1996 ; Takigawa et al., 1996 ), superconductivity (Hiroi et al., 1993 ), ultrafast non-linear optical response (Ogasawara et al., 2000 ) or even glucose sensing (El-Ads et al., 2016 ). The particularly relevant sub-family based on square-planar MO₄ (M = divalent metal) primary building units is dominated by oxidocuprates(II), while the chemistry of respective palladates(II), showing the same preference for a square-planar coordination by oxygen, is much less explored.

Here we address Sr₂PdO₃, which has previously been obtained as a microcrystalline material (Wasel-Nielen & Hoppe, 1970; Muller & Roy, 1971; Nagata et al., 2002). Based on evaluations of powder X-ray diffractograms, Sr₂PdO₃ was identified as being isostructural with Sr₂CuO₃ (Teske & Müller-Buschbaum, 1969 ; Weller & Lines, 1989 ) and Sr₂FeO₃ (Tassel et al., 2013 ). However, structural details derived from the given atomic parameters have only been reported with large uncertainties (Muller & Roy, 1971; Nagata et al., 2002). Therefore, a redetermination of Sr₂PdO₃ based on single crystal X-ray data seemed appropriate.

2. Structural commentary

The crystal structure of Sr₂PdO₃ is essentially the same as determined previously (Wasel-Nielen & Hoppe, 1970; Muller & Roy, 1971; Nagata et al., 2002). The lattice parameters (Table 1) are almost identical to those in the previous reports but with higher precision. The Pd^II atom occupies the 2d crystallographic sites with mmm site symmetry. We would like to point out that we chose a different cell setting as compared to all the previous reports, where the Pd^II atom was chosen to be located at the cell origin (site 2a; 0, 0, 0; hence the different site designations). The Pd^II atom forms distorted PdO₄ square planes, which are linked by sharing oxygen atoms in the trans-position to form infinite chains extending along the b-axis direction as shown in Fig. 1. Corresponding to this connectivity pattern, the Pd—O bond lengths are longer for the shared oxygen atoms, 2.052 (2) Å, and shorter for the terminal ones, 1.9911 (2) Å. The Sr atom is situated at the 4j Wyckoff site having mm2 site symmetry. It is seven-coordinate in a monocapped trigonal–prismatic fashion by oxygen with three different bond lengths (Table 1, Fig. 2). In addition to the square-planar first coordination of Pd^II with oxygen, the second consists of eight Sr^II atoms present at the corner of a cuboid with dimension 3.5342 (2) × 3.7887 (2) × 3.9822 (3) Å³ (Fig. 2). Of the two kinds of oxygen atoms, both surrounded by six metal ions that form distorted octahedra, O1 is coordinated by one Pd^II atom [2.052 (2) Å] and five Sr^II atoms with one short [2.474 (2) Å] and four long distances [2.6668 (2) Å] (Fig. 3). O2 is connected to four equidistant Sr^II [2.5906 (3) Å] and two Pd^II atoms [1.9911 (2) Å] (Fig. 3). In our current structure determination, much more precise values of the cell parameters along with the z parameters of Sr and O1 have been determined, consequently, yielding very precise values for the bond lengths (see Table 1). The quality of the current refinement is also clearly reflected by better reliability factors (see Table 2) as compared to the previous refinements. The atomic arrangement described here is same as provided by Wasel-Nielen & Hoppe (1970).

Table 1
Comparison of lattice parameters and bond lengths (Å) in Sr₂PdO₃ determined in different studies

	1970 work^a	1971 work^b	2002 work^c	This work
a	3.977	3.97	3.985	3.5342 (2)
b	3.53	3.544	3.539	3.9822 (3)
c	12.82	12.84	12.847	12.8414 (8)
Pd—O1 (×2)	2.08	2.045	2.068	2.052 (2)
Pd—O2 (×2)	1.99	1.985	1.993	1.9911 (1)
Sr—O1	2.45	2.504	2.467	2.474 (2)
Sr—O1 (×4)	2.67	2.668	2.671	2.6668 (2)
Sr—O2 (×2)	2.58	2.57	2.588	2.5906 (3)
References: (a) Wasel-Nielen & Hoppe (1970); (b) Muller & Roy (1971); (c) Nagata et al. (2002).

Table 2
Experimental details

Crystal data
Chemical formula	Sr₂PdO₃
M_r	329.64
Crystal system, space group	Orthorhombic, Immm
Temperature (K)	296
a, b, c (Å)	3.5342 (2), 3.9822 (3), 12.8414 (8)
V (Å³)	180.73 (2)
Z	2
Radiation type	Mo Kα
μ (mm⁻¹)	34.15
Crystal size (mm)	0.18 × 0.16 × 0.12

Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2009 )
T_min, T_max	0.062, 0.102
No. of measured, independent and observed [I > 2σ(I)] reflections	8304, 178, 176
R_int	0.035
(sin θ/λ)_max (Å⁻¹)	0.702

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.009, 0.021, 1.27
No. of reflections	178
No. of parameters	16
Δρ_max, Δρ_min (e Å⁻³)	0.43, −0.51
Computer programs: APEX2 and, SAINT (Bruker, 2009), SHELXS97 and SHELXTL (Sheldrick, 2008 ), SHELXL2014/7 (Sheldrick, 2015 ), DIAMOND (Brandenburg, 2006 ).

Figure 1
Crystal structure of Sr₂PdO₃ viewed along the a axis (left) and along the b axis (right).

Figure 2
Coordination around the Sr^II (left) and Pd^II atoms (right). All atoms are drawn with displacement ellipsoids at the 80% probability level. Distances are in Å.

Figure 3
Coordination polyhedra of two types of oxygen atoms, O1 (left) and O2 (right). All atoms are drawn with displacement ellipsoids at the 80% probability level. Distances are in Å.

The structural features discussed above are closely related to those of the K₂NiF₄ type of structure, which is regarded as the prototype structure for all the high T_c cuprates. K₂NiF₄ consists of layers of corner-shared NiF₆ octahedra extending in the ab plane. One can derive the Sr₂PdO₃ structure from the K₂NiF₄ structure by systematically removing the bridging F atoms from the NiF₆ octahedra lying in the a-axis direction (Fig. 4). This would reduce the dimensionality of the layer, resulting in linear chains of square planes connected by edges along only one direction.

Figure 4
Interconversion of the Sr₂PdO₃ and K₂NiF₄ structures.

3. Synthesis and crystallization

Millimeter-sized block-shaped crystals of dark-yellow colour with composition Sr₂PdO₃ as confirmed by SEM–EDS, were obtained from a mixture of different phases while attempting to synthesize SrPd₃O₄ using a KOH flux (Smallwood et al., 2000 ). SrCO₃ and Pd metal powder were mixed in the molar ratio of 2:3, placed in an alumina crucible, and 15 grams of KOH pellets were added on top. The crucible was heated in a muffle furnace to 1023 K in 24 h with a 6 h dwell time. The furnace was then cooled slowly to 873 K over 125 h after which it was switched off and allowed to cool naturally. The product was washed several times with water to remove the solidified flux and subsequently rinsed with ethanol.

4. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2.

Supporting information

CCDC reference: 1882781

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2056989018017176/wm5474sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989018017176/wm5474Isup2.hkl

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014/7 (Sheldrick, 2015); molecular graphics: DIAMOND (Brandenburg, 2006); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Distrontium palladium trioxide top

Crystal data top

Sr₂PdO₃	D_x = 6.057 Mg m⁻³
M_r = 329.64	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Immm	Cell parameters from 1490 reflections
a = 3.5342 (2) Å	θ = 3.2–29.9°
b = 3.9822 (3) Å	µ = 34.15 mm⁻¹
c = 12.8414 (8) Å	T = 296 K
V = 180.73 (2) Å³	Block, yellow-brown
Z = 2	0.18 × 0.16 × 0.12 mm
F(000) = 292

Data collection top

Bruker APEXII CCD diffractometer	176 reflections with I > 2σ(I)
φ and ω scans	R_int = 0.035
Absorption correction: multi-scan (SADABS; Bruker, 2009)	θ_max = 29.9°, θ_min = 3.2°
T_min = 0.062, T_max = 0.102	h = −4→4
8304 measured reflections	k = −5→5
178 independent reflections	l = −18→18

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	w = 1/[σ²(F_o²) + (0.0092P)² + 0.2817P] where P = (F_o² + 2F_c²)/3
R[F² > 2σ(F²)] = 0.009	(Δ/σ)_max < 0.001
wR(F²) = 0.021	Δρ_max = 0.43 e Å⁻³
S = 1.27	Δρ_min = −0.51 e Å⁻³
178 reflections	Extinction correction: SHELXL-2014/7 (Sheldrick, 2015), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
16 parameters	Extinction coefficient: 0.0059 (5)

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
Pd1	0.5000	0.0000	0.5000	0.00493 (11)
Sr1	0.5000	0.0000	0.14752 (2)	0.00656 (11)
O1	0.5000	0.0000	0.34021 (18)	0.0085 (5)
O2	0.5000	0.5000	0.5000	0.0128 (8)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Pd1	0.00765 (19)	0.00396 (17)	0.00320 (18)	0.000	0.000	0.000
Sr1	0.00752 (17)	0.00760 (16)	0.00456 (17)	0.000	0.000	0.000
O1	0.0117 (13)	0.0101 (12)	0.0037 (11)	0.000	0.000	0.000
O2	0.021 (2)	0.0035 (15)	0.0134 (18)	0.000	0.000	0.000

Geometric parameters (Å, º) top

Pd1—O2ⁱ	1.9911 (1)	Sr1—O1^ix	2.6668 (2)
Pd1—O2	1.9911 (1)	Sr1—O1^vii	2.6668 (2)
Pd1—O1	2.052 (2)	Sr1—Pd1^xi	3.2674 (2)
Pd1—O1ⁱⁱ	2.052 (2)	Sr1—Pd1^xii	3.2674 (2)
Pd1—Sr1ⁱⁱⁱ	3.2674 (2)	Sr1—Pd1^xiii	3.2674 (2)
Pd1—Sr1^iv	3.2674 (2)	Sr1—Pd1^xiv	3.2674 (2)
Pd1—Sr1^v	3.2674 (2)	Sr1—Sr1^xv	3.5342 (2)
Pd1—Sr1^vi	3.2674 (2)	O1—Sr1^viii	2.6668 (2)
Pd1—Sr1^vii	3.2674 (2)	O1—Sr1ⁱⁱⁱ	2.6668 (2)
Pd1—Sr1^viii	3.2674 (2)	O1—Sr1^vii	2.6668 (2)
Pd1—Sr1^ix	3.2674 (2)	O1—Sr1^ix	2.6668 (2)
Pd1—Sr1^x	3.2674 (2)	O2—Pd1^xvi	1.9911 (1)
Sr1—O1	2.474 (2)	O2—Sr1^ix	2.5906 (3)
Sr1—O2^xi	2.5906 (3)	O2—Sr1^iv	2.5906 (3)
Sr1—O2^xii	2.5906 (3)	O2—Sr1^viii	2.5906 (3)
Sr1—O1^viii	2.6668 (2)	O2—Sr1^vi	2.5906 (3)
Sr1—O1ⁱⁱⁱ	2.6668 (2)

O2ⁱ—Pd1—O2	180.0	O1—Sr1—O1^vii	86.61 (5)
O2ⁱ—Pd1—O1	90.0	O2^xi—Sr1—O1^vii	119.68 (4)
O2—Pd1—O1	90.0	O2^xii—Sr1—O1^vii	65.87 (4)
O2ⁱ—Pd1—O1ⁱⁱ	90.0	O1^viii—Sr1—O1^vii	96.597 (9)
O2—Pd1—O1ⁱⁱ	90.0	O1ⁱⁱⁱ—Sr1—O1^vii	83.000 (8)
O1—Pd1—O1ⁱⁱ	180.0	O1^ix—Sr1—O1^vii	173.22 (10)
O2ⁱ—Pd1—Sr1ⁱⁱⁱ	52.455 (3)	O1—Sr1—Pd1^xi	125.435 (5)
O2—Pd1—Sr1ⁱⁱⁱ	127.545 (3)	O2^xi—Sr1—Pd1^xi	37.546 (3)
O1—Pd1—Sr1ⁱⁱⁱ	54.565 (5)	O2^xii—Sr1—Pd1^xi	86.845 (8)
O1ⁱⁱ—Pd1—Sr1ⁱⁱⁱ	125.435 (5)	O1^viii—Sr1—Pd1^xi	147.95 (5)
O2ⁱ—Pd1—Sr1^iv	127.545 (3)	O1ⁱⁱⁱ—Sr1—Pd1^xi	38.82 (5)
O2—Pd1—Sr1^iv	52.455 (3)	O1^ix—Sr1—Pd1^xi	97.52 (3)
O1—Pd1—Sr1^iv	125.435 (5)	O1^vii—Sr1—Pd1^xi	86.43 (3)
O1ⁱⁱ—Pd1—Sr1^iv	54.565 (5)	O1—Sr1—Pd1^xii	125.435 (5)
Sr1ⁱⁱⁱ—Pd1—Sr1^iv	180.0	O2^xi—Sr1—Pd1^xii	86.845 (8)
O2ⁱ—Pd1—Sr1^v	52.455 (4)	O2^xii—Sr1—Pd1^xii	37.546 (3)
O2—Pd1—Sr1^v	127.545 (3)	O1^viii—Sr1—Pd1^xii	97.52 (3)
O1—Pd1—Sr1^v	125.435 (5)	O1ⁱⁱⁱ—Sr1—Pd1^xii	86.43 (3)
O1ⁱⁱ—Pd1—Sr1^v	54.565 (5)	O1^ix—Sr1—Pd1^xii	147.95 (5)
Sr1ⁱⁱⁱ—Pd1—Sr1^v	70.871 (10)	O1^vii—Sr1—Pd1^xii	38.82 (5)
Sr1^iv—Pd1—Sr1^v	109.129 (10)	Pd1^xi—Sr1—Pd1^xii	65.481 (6)
O2ⁱ—Pd1—Sr1^vi	127.545 (3)	O1—Sr1—Pd1^xiii	125.435 (5)
O2—Pd1—Sr1^vi	52.455 (4)	O2^xi—Sr1—Pd1^xiii	86.845 (9)
O1—Pd1—Sr1^vi	125.435 (5)	O2^xii—Sr1—Pd1^xiii	37.546 (3)
O1ⁱⁱ—Pd1—Sr1^vi	54.565 (5)	O1^viii—Sr1—Pd1^xiii	38.82 (5)
Sr1ⁱⁱⁱ—Pd1—Sr1^vi	114.520 (6)	O1ⁱⁱⁱ—Sr1—Pd1^xiii	147.95 (5)
Sr1^iv—Pd1—Sr1^vi	65.480 (6)	O1^ix—Sr1—Pd1^xiii	86.43 (3)
Sr1^v—Pd1—Sr1^vi	75.090 (7)	O1^vii—Sr1—Pd1^xiii	97.52 (3)
O2ⁱ—Pd1—Sr1^vii	52.455 (3)	Pd1^xi—Sr1—Pd1^xiii	109.130 (10)
O2—Pd1—Sr1^vii	127.545 (3)	Pd1^xii—Sr1—Pd1^xiii	75.091 (7)
O1—Pd1—Sr1^vii	54.565 (5)	O1—Sr1—Pd1^xiv	125.435 (5)
O1ⁱⁱ—Pd1—Sr1^vii	125.435 (5)	O2^xi—Sr1—Pd1^xiv	37.546 (3)
Sr1ⁱⁱⁱ—Pd1—Sr1^vii	65.480 (5)	O2^xii—Sr1—Pd1^xiv	86.845 (8)
Sr1^iv—Pd1—Sr1^vii	114.520 (6)	O1^viii—Sr1—Pd1^xiv	86.43 (3)
Sr1^v—Pd1—Sr1^vii	104.910 (7)	O1ⁱⁱⁱ—Sr1—Pd1^xiv	97.52 (3)
Sr1^vi—Pd1—Sr1^vii	180.0	O1^ix—Sr1—Pd1^xiv	38.82 (5)
O2ⁱ—Pd1—Sr1^viii	127.545 (3)	O1^vii—Sr1—Pd1^xiv	147.95 (5)
O2—Pd1—Sr1^viii	52.455 (3)	Pd1^xi—Sr1—Pd1^xiv	75.091 (7)
O1—Pd1—Sr1^viii	54.565 (5)	Pd1^xii—Sr1—Pd1^xiv	109.130 (10)
O1ⁱⁱ—Pd1—Sr1^viii	125.435 (5)	Pd1^xiii—Sr1—Pd1^xiv	65.481 (6)
Sr1ⁱⁱⁱ—Pd1—Sr1^viii	109.129 (10)	O1—Sr1—Sr1^xv	90.0
Sr1^iv—Pd1—Sr1^viii	70.871 (10)	O2^xi—Sr1—Sr1^xv	133.011 (5)
Sr1^v—Pd1—Sr1^viii	180.0	O2^xii—Sr1—Sr1^xv	46.991 (5)
Sr1^vi—Pd1—Sr1^viii	104.910 (7)	O1^viii—Sr1—Sr1^xv	48.500 (3)
Sr1^vii—Pd1—Sr1^viii	75.090 (7)	O1ⁱⁱⁱ—Sr1—Sr1^xv	131.500 (4)
O2ⁱ—Pd1—Sr1^ix	127.545 (4)	O1^ix—Sr1—Sr1^xv	131.500 (4)
O2—Pd1—Sr1^ix	52.455 (3)	O1^vii—Sr1—Sr1^xv	48.500 (4)
O1—Pd1—Sr1^ix	54.565 (5)	Pd1^xi—Sr1—Sr1^xv	122.741 (3)
O1ⁱⁱ—Pd1—Sr1^ix	125.435 (5)	Pd1^xii—Sr1—Sr1^xv	57.260 (3)
Sr1ⁱⁱⁱ—Pd1—Sr1^ix	75.090 (7)	Pd1^xiii—Sr1—Sr1^xv	57.260 (3)
Sr1^iv—Pd1—Sr1^ix	104.910 (7)	Pd1^xiv—Sr1—Sr1^xv	122.741 (3)
Sr1^v—Pd1—Sr1^ix	114.520 (6)	Pd1—O1—Sr1	180.0
Sr1^vi—Pd1—Sr1^ix	70.871 (10)	Pd1—O1—Sr1^viii	86.61 (5)
Sr1^vii—Pd1—Sr1^ix	109.129 (10)	Sr1—O1—Sr1^viii	93.39 (5)
Sr1^viii—Pd1—Sr1^ix	65.480 (6)	Pd1—O1—Sr1ⁱⁱⁱ	86.61 (5)
O2ⁱ—Pd1—Sr1^x	52.455 (3)	Sr1—O1—Sr1ⁱⁱⁱ	93.39 (5)
O2—Pd1—Sr1^x	127.545 (3)	Sr1^viii—O1—Sr1ⁱⁱⁱ	173.23 (10)
O1—Pd1—Sr1^x	125.435 (5)	Pd1—O1—Sr1^vii	86.61 (5)
O1ⁱⁱ—Pd1—Sr1^x	54.565 (5)	Sr1—O1—Sr1^vii	93.39 (5)
Sr1ⁱⁱⁱ—Pd1—Sr1^x	104.910 (7)	Sr1^viii—O1—Sr1^vii	96.597 (9)
Sr1^iv—Pd1—Sr1^x	75.090 (7)	Sr1ⁱⁱⁱ—O1—Sr1^vii	83.001 (8)
Sr1^v—Pd1—Sr1^x	65.480 (5)	Pd1—O1—Sr1^ix	86.61 (5)
Sr1^vi—Pd1—Sr1^x	109.129 (10)	Sr1—O1—Sr1^ix	93.39 (5)
Sr1^vii—Pd1—Sr1^x	70.871 (10)	Sr1^viii—O1—Sr1^ix	83.001 (8)
Sr1^viii—Pd1—Sr1^x	114.520 (6)	Sr1ⁱⁱⁱ—O1—Sr1^ix	96.597 (9)
Sr1^ix—Pd1—Sr1^x	180.0	Sr1^vii—O1—Sr1^ix	173.23 (10)
O1—Sr1—O2^xi	136.990 (5)	Pd1^xvi—O2—Pd1	180.0
O1—Sr1—O2^xii	136.990 (5)	Pd1^xvi—O2—Sr1^ix	90.0
O2^xi—Sr1—O2^xii	86.020 (11)	Pd1—O2—Sr1^ix	90.0
O1—Sr1—O1^viii	86.61 (5)	Pd1^xvi—O2—Sr1^iv	90.0
O2^xi—Sr1—O1^viii	119.68 (4)	Pd1—O2—Sr1^iv	90.0
O2^xii—Sr1—O1^viii	65.87 (4)	Sr1^ix—O2—Sr1^iv	180.0
O1—Sr1—O1ⁱⁱⁱ	86.61 (5)	Pd1^xvi—O2—Sr1^viii	90.0
O2^xi—Sr1—O1ⁱⁱⁱ	65.87 (4)	Pd1—O2—Sr1^viii	90.0
O2^xii—Sr1—O1ⁱⁱⁱ	119.68 (4)	Sr1^ix—O2—Sr1^viii	86.018 (11)
O1^viii—Sr1—O1ⁱⁱⁱ	173.22 (10)	Sr1^iv—O2—Sr1^viii	93.982 (11)
O1—Sr1—O1^ix	86.61 (5)	Pd1^xvi—O2—Sr1^vi	90.0
O2^xi—Sr1—O1^ix	65.87 (4)	Pd1—O2—Sr1^vi	90.0
O2^xii—Sr1—O1^ix	119.68 (4)	Sr1^ix—O2—Sr1^vi	93.982 (11)
O1^viii—Sr1—O1^ix	83.000 (8)	Sr1^iv—O2—Sr1^vi	86.018 (11)
O1ⁱⁱⁱ—Sr1—O1^ix	96.597 (9)	Sr1^viii—O2—Sr1^vi	180.0

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

Comparison of lattice parameters and bond lengths (Å) in Sr₂PdO₃ determined in different studies top

	1970 work^a	1971 work^b	2002 work^c	This work
a	3.977	3.97	3.985	3.5342 (2)
b	3.53	3.544	3.539	3.9822 (3)
c	12.82	12.84	12.847	12.8414 (8)
Pd—O1 (×2)	2.08	2.045	2.068	2.052 (2)
Pd—O2 (×2)	1.99	1.985	1.993	1.9911 (1)
Sr—O1	2.45	2.504	2.467	2.474 (2)
Sr—O1 (×4)	2.67	2.668	2.671	2.6668 (2)
Sr—O2 (×2)	2.58	2.57	2.588	2.5906 (3)

References: (a) Wasel-Nielen & Hoppe (1970); (b) Muller & Roy (1971); (c) Nagata et al. (2002).

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