MAGNDATA - Collection of Magnetic Structures

MAGNDATA

Collection of Magnetic Structures

MAGNDATA: A Collection of magnetic structures with portable cif-type files

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Magnetic structure with all atoms

Magnetic structure with only magnetic atoms

N	(x,y,z)	Seitz notation
1	x,y,z,+1	{ 1 \| 0 }
2	x+1/2,-y+1/2,-z,+1	{ 2₁₀₀ \| 1/2 1/2 0 }
3	-x,-y,-z,+1	{ -1 \| 0 }
4	-x+1/2,y+1/2,z,+1	{ m₁₀₀ \| 1/2 1/2 0 }
5	-x+1/2,y+1/2,-z+1/2,-1	{ 2'₀₁₀ \| 1/2 1/2 1/2 }
6	-x,-y,z+1/2,-1	{ 2'₀₀₁ \| 0 0 1/2 }
7	x+1/2,-y+1/2,z+1/2,-1	{ m'₀₁₀ \| 1/2 1/2 1/2 }
8	x,y,-z+1/2,-1	{ m'₀₀₁ \| 0 0 1/2 }

N	(x,y,z)	Seitz notation
1	x,y,z,+1	1
2	x,-y,-z,+1	2₁₀₀
3	-x,-y,-z,+1	-1
4	-x,y,z,+1	m₁₀₀
5	-x,y,-z,-1	2'₀₁₀
6	-x,-y,z,-1	2'₀₀₁
7	x,-y,z,-1	m'₀₁₀
8	x,y,-z,-1	m'₀₀₁

Label	Atom type	x	y	z	Multiplicity
O1	O	-0.08495	0.47692	0.25000	4
O2	O	0.29733	0.29490	0.04443	8

Atom	x	y	z	Symmetry constraints on M	M_y	M_z
1	0.50000	0.00000	0.00000	m_x,m_y,m_z	0.20000	2.98000
2	0.00000	0.50000	0.00000	m_x,-m_y,-m_z	-0.20000	-2.98000
3	0.00000	0.50000	0.50000	m_x,-m_y,m_z	-0.20000	2.98000
4	0.50000	0.00000	0.50000	m_x,m_y,-m_z	0.20000	-2.98000

Atom	x	y	z	Symmetry constraints on M	M_y
1	0.01362	0.03649	0.25000	m_x,m_y,0	0.53000
2	0.51362	0.46351	0.75000	m_x,-m_y,0	-0.53000
3	0.98638	0.96351	0.75000	m_x,m_y,0	0.53000
4	0.48638	0.53649	0.25000	m_x,-m_y,0	-0.53000

Atom	x	y	z
1	0.91505	0.47692	0.25000
2	0.41505	0.02308	0.75000
3	0.08495	0.52308	0.75000
4	0.58495	0.97692	0.25000

Atom	x	y	z
1	0.29733	0.29490	0.04443
2	0.79733	0.20510	0.95557
3	0.70267	0.70510	0.95557
4	0.20267	0.79490	0.04443
5	0.20267	0.79490	0.45557
6	0.70267	0.70510	0.54443
7	0.79733	0.20510	0.54443
8	0.29733	0.29490	0.45557

Reference: T. Sau, P. Yadav, S. Sharma, R. Raghunathan, P. Manuel, V. Petricek, U. P. Deshpande, N. P. Lalla, PHYSICAL REVIEW B (2021) 103 144418
DOI: 10.1103/PhysRevB.103.144418
Atomic positions from: same reference

Parent space group (paramagnetic phase): Pbnm (#62) (non-standard)
Transformation to a standard setting: (b,c,a;0,0,0)
    [View matrix form]
Propagation vector: k1 (0, 0, 0)

Transition Temperature: 37 K
Experiment Temperature: 1.5 K

Lattice parameters of the magnetic unit cell:
5.3624(1) 5.4907(1) 7.6316(3) 90.00000 90.00000 90.00000
Transformation from parent structure: (a,b,c;0,0,0)
    [View matrix form]

BNS Magnetic Space Group: Pbn'm' (#62.446) (non-standard)
    [View symmetry operations]
Transformation to a standard setting: (b,c,a;0,0,0)
    [View matrix form]
Systematic absences for this Magnetic Space Group via

Magnetic Point Group: m'm'm (8.4.27)
    [View symmetry operations]
Symmetry-adapted form of material tensors via
Symmetry-adapted form of material tensors for domain-related equivalent structures via

Positions and magnetic moments of symmetry independent atoms:
From now on, magnetic atoms are in boldface and colored in red. Magnetic moments are expressed in units of μB

     [Show only magnetic atoms]                                             Use MVISUALIZE to:
     [Show all the atoms]

Label	Atom type	x	y	z	Multiplicity	Symmetry constraints on M	M_x	M_y	M_z	\|M\|
Cr1	Cr	0.50000	0.00000	0.00000	4	M_x,M_y,M_z	0.0	0.2(1)	2.98(3)	2.99
Sm1	Sm	0.01362	0.03649	0.25000	4	M_x,M_y,0	0.0	0.53(8)	0.0	0.53

Atom	x	y	z	Symmetry constraints on M	M_y	M_z
1	0.50000	0.00000	0.00000	m_x,m_y,m_z	0.20000	2.98000
2	0.00000	0.50000	0.00000	m_x,-m_y,-m_z	-0.20000	-2.98000
3	0.00000	0.50000	0.50000	m_x,-m_y,m_z	-0.20000	2.98000
4	0.50000	0.00000	0.50000	m_x,m_y,-m_z	0.20000	-2.98000

Atom	x	y	z	Symmetry constraints on M	M_y
1	0.01362	0.03649	0.25000	m_x,m_y,0	0.53000
2	0.51362	0.46351	0.75000	m_x,-m_y,0	-0.53000
3	0.98638	0.96351	0.75000	m_x,m_y,0	0.53000
4	0.48638	0.53649	0.25000	m_x,-m_y,0	-0.53000

[Show all magnetic atoms in unit cell and their moment relations]

Active Irreps:

label	dim. small irrep	dim. full irrep	action	number of modes
mGM2+	1	1	primary	4

Comments:

NPD
Other magnetic phase at higher temperatures, between 192K and 37K (see #0.696).
Non-standard parent setting Pbnm
This structure was refined and reported under the MSG P2_1'2_1'2_1 in its standard setting related according to: b,c,a;1/2,0,0, with respect to the Pbnm parent setting. All small parameters with very large errors in a first fit were constrained to zero.
The structure has in fact a larger symmetry described by the MSG Pn'm'a (Pbn'm' in the parent setting), the same MSG as in the structure reported at 25K (see #0.697). Therefore the claim of a symmetry breaking transition between this temperature and 1.5K is not supported by the structure being reported.
Here we describe the structure under its correct MSG, keeping the parent setting.
FM along a (Pbnm setting)
Contrary to the statement in the paper, this structure is NOT polar
A second model under the MSG Pn'a2_1' (standard setting: -b,a,c;0,0,0 with respect to the Pbnm seeting) is reported to fit the data nearly equally well. This second model however suffers the same defect: its actual symmetry is given again by the higher MSG Pn'm'a (Pbn'm' in the parent setting), as the only degree of freedom breaking this symmetry is constrained to zero, after showing a negligible value in an unconstrained fit. This assumedly alternative second model is in fact essentially equivalent to the first one described here, except for the small non-zero my component of the Cr moment, which was constrained to zero in the supposedly alternative model.
See #0.478 for a different structure at 2K, which has been proposed for the same phase. This alternative model has a different MSG not allowing FM.

Comments (symmetry):

1k magnetic structure
k-maximal magnetic symmetry
1-dim irrep as primary

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MAGNDATA: A Collection of magnetic structures with portable cif-type files

SmCrO3 (#0.698)

SmCrO₃ (#0.698)