MAGNDATA - Collection of Magnetic Structures

Magnetic structure with only magnetic atoms

N	(x,y,z)	Seitz notation
1	x1,x2,x3,x4,+1	{ 1 \| 0 }
(1/2,1/2,0,0) + set click here to show and hide
2	x1+1/2,x2+1/2,x3,x4,+1	{ 1 \| 1/2 1/2 0 0 }
(0,0,0,1/2)' + set click here to show and hide
3	x1,x2,x3,x4+1/2,-1	{ 1' \| 0 0 0 1/2 }
(1/2,1/2,0,1/2)' + set click here to show and hide
4	x1+1/2,x2+1/2,x3,x4+1/2,-1	{ 1' \| 1/2 1/2 0 1/2 }

N	(x,y,z)	Seitz notation
1	x,y,z,+1	1
1' + set click here to show and hide
2	x,y,z,-1	1'

Label	Atom type	x	y	z	Multiplicity
Li1	Li	0	0.617	0	2
As1_1	As	0.7824	0.337	0.591	2
As1_2	As	0.21760	0.33700	0.409	2
O1_1	O	0.7497	0.4811	0.8237	2
O1_2	O	0.25030	0.48110	0.1763	2
O2_1	O	0.831	0.1567	0.7473	2
O2_2	O	0.16900	0.15670	0.2527	2
O3_1	O	0.61	0.317	0.2773	2
O3_2	O	0.39000	0.31700	0.72270	2
O4	O	0	0.4147	0.5	2

Atom	Magnetic moment Fourier Cos coeffs	Magnetic moment Fourier Sin coeffs
Symmetry constraints	Numerical values	Symmetry constraints	Numerical values
x	y	z	x	y	z	x	y	z	x	y	z
Fe1	M_xcos1	M_ycos1	M_zcos1	-1.733	0.290	-4.343	M_xsin1	M_ysin1	0.0	-1.672	-3.939	0.0

Atom	x	y	z
1	0.00000	0.00000	0.00000
(1/2,1/2,0,0) + set click here to show and hide
2	0.50000	0.50000	0.00000

Atom	Magnetic moment Fourier Cos coeffs	Magnetic moment Fourier Sin coeffs
Symmetry constraints	Numerical values	Symmetry constraints	Numerical values
x	y	z	x	y	z	x	y	z	x	y	z
1	M_xcos1	M_ycos1	M_zcos1	-1.73300	0.29000	-4.34300	M_xsin1	M_ysin1	0	-1.67200	-3.93900	0.0
(1/2,1/2,0,0) + set click here to show and hide
2	M_xcos1	M_ycos1	M_zcos1	-1.73300	0.29000	-4.34300	M_xsin1	M_ysin1	0	-1.67200	-3.93900	0.0

Atom	x	y	z
1	0.00000	0.61700	0.00000
(1/2,1/2,0,0) + set click here to show and hide
2	0.50000	0.11700	0.00000

Atom	x	y	z
1	0.78240	0.33700	0.59100
(1/2,1/2,0,0) + set click here to show and hide
2	0.28240	0.83700	0.59100

Atom	x	y	z
1	0.21760	0.33700	0.40900
(1/2,1/2,0,0) + set click here to show and hide
2	0.71760	0.83700	0.40900

Atom	x	y	z
1	0.74970	0.48110	0.82370
(1/2,1/2,0,0) + set click here to show and hide
2	0.24970	0.98110	0.82370

Atom	x	y	z
1	0.25030	0.48110	0.17630
(1/2,1/2,0,0) + set click here to show and hide
2	0.75030	0.98110	0.17630

Atom	x	y	z
1	0.83100	0.15670	0.74730
(1/2,1/2,0,0) + set click here to show and hide
2	0.33100	0.65670	0.74730

Atom	x	y	z
1	0.16900	0.15670	0.25270
(1/2,1/2,0,0) + set click here to show and hide
2	0.66900	0.65670	0.25270

Atom	x	y	z
1	0.61000	0.31700	0.27730
(1/2,1/2,0,0) + set click here to show and hide
2	0.11000	0.81700	0.27730

Atom	x	y	z
1	0.39000	0.31700	0.72270
(1/2,1/2,0,0) + set click here to show and hide
2	0.89000	0.81700	0.72270

Atom	x	y	z
1	0.00000	0.41470	0.50000
(1/2,1/2,0,0) + set click here to show and hide
2	0.50000	0.91470	0.50000

Reference: G. Rousse, J. Rodriguez-Carvajal, C. Wurm and C. Masquelier, Physical Review B (2013) 88 214433.
DOI: 10.1103/physrevb.88.214433
Atomic positions from: same reference

Parent space group (paramagnetic phase): C2 (#5)
Propagation vector: k1 (0.709000, 0.000000, 0.155000)

Transition Temperature: 35 K
Experiment Temperature: 2 K

Lattice parameters of the basic unit cell:
6.6786(1) 8.2855(1) 4.7429(1) 90 103.950(1) 90
Transformation from parent structure: (a,b,c;0,0,0)
    [View matrix form]

Magnetic Superspace Group: C11'(αβγ)0s
    [View symmetry operations]

Magnetic Point Group: 11' (1.2.2)
    [View symmetry operations]
Symmetry-adapted form of material tensors via

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

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     [Show all the atoms]

Average atomic positions of symmetry independent atoms

Label	Atom type	x	y	z	Multiplicity
Fe1	Fe	0	0	0	2

Magnetic moment modulation parameters of symmetry independent atoms

Wave vector 1

Atom	Magnetic moment Fourier Cos coeffs						Magnetic moment Fourier Sin coeffs
	Symmetry constraints			Numerical values			Symmetry constraints			Numerical values
	x	y	z	x	y	z	x	y	z	x	y	z
Fe1	M_xcos1	M_ycos1	M_zcos1	-1.733	0.290	-4.343	M_xsin1	M_ysin1	0.0	-1.672	-3.939	0.0

Atom	x	y	z
1	0.00000	0.00000	0.00000
(1/2,1/2,0,0) + set click here to show and hide
2	0.50000	0.50000	0.00000

Atom	Magnetic moment Fourier Cos coeffs	Magnetic moment Fourier Sin coeffs
Symmetry constraints	Numerical values	Symmetry constraints	Numerical values
x	y	z	x	y	z	x	y	z	x	y	z
1	M_xcos1	M_ycos1	M_zcos1	-1.73300	0.29000	-4.34300	M_xsin1	M_ysin1	0	-1.67200	-3.93900	0.0
(1/2,1/2,0,0) + set click here to show and hide
2	M_xcos1	M_ycos1	M_zcos1	-1.73300	0.29000	-4.34300	M_xsin1	M_ysin1	0	-1.67200	-3.93900	0.0

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

Comments:

NPD
atomic positions from room temperature measurement.
Fe mooment modulus: 4.28(3)

Comments (symmetry):

The arbitrary phase of the modulation is chosen by fixing the z sine component of the Fe spin modulation to be zero.
The vector amplitude of the cosine modulation component is nearly perpendicular to the one of the sine modulation so that the modulation only rotates the moment without changing its modulus. This is not symmetry forced.
The spins rotate on a plane given by a rather arbitrary direction. The fit cannot distinguish between two models with with different orientation of the spin rotation plane. This is the first of the two models.
A single (irrep) mode (even if only one single irrep exists) would force this rotation plane to contain the monoclinic axis and the point-group symmetry would then keep the binary axis, the corresponding MSSG being monoclinic.
The reason why the higher symmetry corresponding to a single irrep mode is not realized is not clear (a single phase transition is reported).

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