perovskite atlas Structures, modes and phase transitions · Josu M. Igartua · UPV/EHU

Sr2Co0.9Mg0.1TeO6 · P21/n · 300 K

Sr2Co0.9Mg0.1TeO6 · P21/n · 300 K

status published · visibility public · id str:sr2co0.9mg0.1teo6.p21n.300k.orayech2015

Material
Sr2Co0.9Mg0.1TeO6
Space group
P21/n · No. 14
Setting
P 1 21/n 1 (non-standard setting of No. 14)
Phase
room temperature
Temperature
300 K

fer document ↗ standardised version of this record

Cell

a (Å) b (Å) c (Å) α (°) β (°) γ (°) V (ų)
5.6417(1) 5.6074(1) 7.9213(1) 90 89.952(4) 90 250.93(1)

Atoms

label element Wyckoff x y z occ. Biso (Ų)
Sr Sr 4e -0.0015(4) 0.4970(1) 0.2521(1) 1 1.03(2)
O1 O 4e -0.7721(1) 0.2536(1) -0.0271(1) 1 1.32(1)
O2 O 4e -0.4533(4) 0.4973(1) -0.2596(5) 1 1.32(1)
O3 O 4e -0.2437(1) 0.2359(1) 0.0242(1) 1 1.32(2)
Te Te 2a 0 0 0 1 0.74(3)
Co/Mg Co 2b 0 0 0.5 0.9/0.1 (Co/Mg) 0.74(3)

Structure for calculations

CIF: absent. Bilbao Crystallographic Server input (AMPLIMODES, SYMMODES, PSEUDO), uncertainties stripped:

# Perovskite Atlas · str:sr2co0.9mg0.1teo6.p21n.300k.orayech2015
# Space group P2_1/n (No. 14) · setting: P 1 21/n 1 (non-standard setting of No. 14)
# BCS structure format: space-group number / cell / number of atoms / element index Wyckoff x y z
14
5.6417 5.6074 7.9213 90 89.952 90
6
Sr 1 4e -0.0015 0.4970 0.2521   # Sr
O 1 4e -0.7721 0.2536 -0.0271   # O1
O 2 4e -0.4533 0.4973 -0.2596   # O2
O 3 4e -0.2437 0.2359 0.0242   # O3
Te 1 2a 0 0 0   # Te
Co 1 2b 0 0 0.5   # Co/Mg, occupancy 0.9/0.1 (Co/Mg)
Copy

Refinement

software method variant Rp Rwp Rexp RBragg χ² parameters
FullProf symmetry-mode all-modes 5.98

Symmetry-mode decomposition

fer document ↗ standardised version of this record

Parent
Fm3m
Transformation
a+b, -a+b, c (Table 9.1; origin shift as given there)
Software
AMPLIMODES
Convention
amplimodes-cell
Variant
all-modes
irrep k direction dim isotropy subgroup amplitude (Å) role physical meaning
GM1+ (0,0,0) 1 Fm3m 0.1833(4)
GM3+ (0,0,0) 1 I4/mmm 0.0007(1)
GM4+ (0,0,0) 1 C2/m 0.7770(1) primary octahedral rotation about the monoclinic b axis (pseudo-cubic [110])
GM5+ (0,0,0) 4 C2/m 0.0630(1)
X2+ (0,1,0) 1 P42/mnm 0.0165(5)
X3+ (0,1,0) 1 P4/mnc 0.1737(5) primary octahedral rotation about c
X5+ (0,1,0) 3 Pnnm 0.0469(5) octahedral rotation about a and A-site displacement along b

Geometry (as reported)

fer document ↗ standardised version of this record

Octahedra: bond lengths, mean and predicted (bond-valence) distances, volumes

octahedron bond length (Å) predicted (Å) V (ų)
Co/MgO6 mean 2.074(1) 2.0985
TeO6 mean 1.923(1) 1.9170

Bond lengths

bond length (Å)
Co/Mg-O1(×2) 2.067(3)
Co/Mg-O2(×2) 2.073(4)
Co/Mg-O3(×2) 2.081(3)
Te-O1(×2) 1.927(3)
Te-O2(×2) 1.922(3)
Te-O3(×2) 1.919(4)

Bond angles

angle value (°)
O1-Co/Mg-O2 89.8(4)
O1-Co/Mg-O3 88.1(3)
O2-Co/Mg-O3 89.2(4)
O1-Te-O2 89.8(4)
O1-Te-O3 89.9(4)
O2-Te-O3 89.0(4)
Co/Mg-O1-Te 168.6(2)
Co/Mg-O2-Te 164.6(2)
Co/Mg-O3-Te 167.0(2)

Column (a) of Table 9.3 (all mode amplitudes refined). Te and Co/Mg have no refined coordinates (special positions); their Wyckoff labels are assigned from the space-group setting and marked fixed. Original FullProf files expected from data rescue.

Evidence