#
Magnetic Structure of Inorganic–Organic Hybrid (C_{6}H_{5}CH_{2}CH_{2}NH_{3})_{2}MnCl_{4} Using Magnetic Space Group Concept

^{1}

^{2}

^{3}

^{4}

^{5}

^{*}

## Abstract

**:**

_{6}H

_{5}CH

_{2}CH

_{2}NH

_{3})

_{2}MnCl

_{4}(Mn-PEA) is antiferromagnetic below 44 K by using magnetic susceptibility and neutron diffraction measurements. Generally, when an antiferromagnetic system is investigated by the neutron diffraction method, half-integer forbidden peaks, which indicate an enlargement of the magnetic cell compared to the chemical cell, should be present. However, in the case of the title compound, integer forbidden peaks are observed, suggesting that the size of the magnetic cell is the same as that of the chemical cell. This phenomenon was until now only theoretically predicted. During our former study, using an irreducible representation method, we suggested that four spin arrangements could be possible candidates and a magnetic cell and chemical cell should coincide. Recently, a magnetic structure analysis employing a magnetic space group has been developed. To confirm our former result by the representation method, in this work we employed a magnetic space group concept, and from this analysis, we show that the magnetic cell must coincide with the nuclear cell because only the Black–White 1 group (equi-translation or same translation group) is possible.

## 1. Introduction

_{6}H

_{5}CH

_{2}CH

_{2}NH

_{3})

_{2}CoCl

_{4}(Co-PEA), (C

_{6}H

_{5}CH

_{2}CH

_{2}NH

_{3})

_{2}MnCl

_{4}(Mn-PEA) and (C

_{6}H

_{5}CH

_{2}CH

_{2}NH

_{3})

_{2}CuCl

_{4}(Cu-PEA) have been solved by the X-ray single crystal diffraction technique [5,6,7]. Co-PEA crystallizes in a monoclinic space group P12

_{1}/c1 (No. 14), and shows no magnetic ordering at all at low temperature. Co builds an isolated tetrahedron with Cl and between inorganic and organic parts various hydrogen bonds exist. Unlike Co-PEA, Mn-PEA and Cu-PEA show an orthorhombic space group Pbca (No.61) and magnetic ordering process occurs at T

_{C}= 10 K for Cu-PEA and at T

_{N}= 44 K for Mn-PEA. Cu-PEA and Mn-PEA belong to the 2-dimensional layered inorganic–organic K

_{2}NiF

_{4}perovskite type of general formula A

_{2}MX

_{4}, where A = organic cation, M = divalent metal and X = halide. Perovskite is the mineral name for CaTiO

_{3}. However, in general, ABX

_{3}or A

_{2}BX

_{4}type compounds are known as perovskite type. The ABX

_{3}type is 3-dimensional and A

_{2}BX

_{4}is a double layered type. The K

_{2}NiF

_{4}-type materials are also known as Ruddlesden–Popper-type compounds [8]. Although both of the abovementioned Cu-PEA and Mn-PEA are of a magnetically ordered phase below a certain temperature, we prefer Mn-PEA, because Mn-PEA is antiferromagnetic and an antiferromagnetic system is more suitable for handling with neutron diffraction techniques. Additionally, in general, an antiferromagnetic system shows forbidden half-integer peaks below a magnetic transition temperature. However, in the case of Mn-PEA, no half-integer forbidden peaks are observed below the Neel temperature. Instead, integer forbidden peaks that have originated from the magnetic phase transition are present. Based on a theoretical study [9], if weak-ferromagnetism or ferrimagnetism by spin canting due to DM (Dzyaloshinsky-Moriya) interactions is present, the antiferromagnetic cell should be same as the chemical cell. Mn-PEA shows antiferromagnetic phase transition at around 44 K and, in addition, spin canting due to DM interactions causes a weak-ferromagnetism or ferrimagnetism [6]. Thus, this compound should be the ideal candidate material with which the theoretical prediction could be proven. In the previous study, we reported not only X-ray single-crystal structure, but also magnetic properties using magnetic susceptibility and neutron diffraction methods combined with irreducible representation techniques. However, a new approach using a magnetic space group has recently been developed. To check and confirm our previous result using a representation method, in this study, we used a magnetic space group concept, and from this analysis, we will show that the magnetic cell in Mn-PEA is the same as a chemical cell.

## 2. Materials and Methods

## 3. Results and Discussion

_{mmm}= {1, i, 2, m, 2

_{x}, 2

_{y}, m

_{x}, m

_{y}}, where i is inversion symmetry, 2

_{x}is a 2-fold symmetry operation along the x-axis and m

_{x}is a mirror-symmetry operation perpendicular to the x-axis. The possible subgroups of the mmm point group with index 2 are 222, mm2 and 2/m, as already mentioned above. If we denote one subgroup as H, the first subgroup can be written for example as H1 = 222 = {1, 2, 2

_{x}, 2

_{y}}. Analogously, we can denote H2 = mm2 = {1, m

_{x}, m

_{y}, 2} and H3 = 2/m = {1, i, 2, m}. In the first case, the magnetic point group M

_{m’m’m’}can be obtained from {1, 2, 2

_{x}, 2

_{y}} + {i, m, m

_{x}, m

_{y}}1′ (see Table 1). This is described as {1, 2, 2

_{x}, 2

_{y}, i’, m’, m’

_{x}, m’

_{y}} = 2/m’2/m’2/m’ = m’m’m’ [10]. This magnetic point group is not compatible with ferromagnetism, because if we look at Table 1, half of the spins have the same sign and the rest of the spins have an opposite sign. This means an antiferromagnetic ordering. Thus, ferromagnetic ordering is impossible in this magnetic point group. This argument is valid for the rest of magnetic point groups. The second one is {1, 2, m

_{x}, m

_{y}} + {i, m, 2

_{x}, 2

_{y}}1′ = {1, 2, 2′

_{x}, 2′

_{y}, i, m’, m

_{x}, m

_{y}} = 2′/m2′/m2/m’ = mmm’ (see Table 1). This magnetic point group is also not compatible with ferromagnetism. In the third case, the corresponding magnetic point group M

_{m’m’2}can be obtained from {1, 2, i, m} + {2

_{y}, m

_{y}, m

_{x}, 2

_{x}}1′ (see Table 1). This can be rewritten as {1, 2, i, m, 2′

_{y}, m’

_{y}, m’

_{x}, 2′x} = 2′/m2′/m2/m = m’m’2. This point group is compatible with ferromagnetism. The magnetic point group m’m’2 is similar to the previous two magnetic point groups. However, if we consider the magnetic moment along the c-axis, all magnetic components along the c-axis show a positive sign. This means that the ferromagnetic ordering in this point group is only possible along the c-axis. Along another two directions, namely the a- and b-axes, antiferromagnetic ordering is possible. The above results are summarized in Table 1. If the determinant value of the matrix of a symmetry operation is +1, it is known as proper rotation, and if this value is −1, then this is an improper rotation.

_{1}, Pb2

_{1}a, P2

_{1}ca, P2

_{1}2

_{1}2

_{1}, P112

_{1}/a, P12

_{1}/c1 and P2

_{1}/b11. Based on the magnetic space group approach, the magnetic cell must coincide with the nuclear cell, because only the Black–White1 group (type 3, which corresponds to the translationengleich group–maximal non-isomorphic subgroup I) is possible. This means that the propagation vector should be (0 0 0) and this has already been observed in our previous neutron diffraction experiment [12]. To denote a magnetic space group, two notations are used: Opechowski–Guccione (OG) and Belov–Neronova–Smirnova (BNS). The only difference can be found in the magnetic lattice description and Black–White 2 groups. While BNS notation does not use the primed element in the group symbol, the primed element can be obtained from the magnetic lattice type [14]. Based on the parent space group, we can obtain five possible magnetic space groups: Pbca, Pbca1′, Pb’ca, Pb’c’a and Pb’c’a’. The general positions of each magnetic space group are shown in Table 2.

_{x}, m

_{y}, m

_{z}), (1/2, 1/2, 0 | m

_{x}, −m

_{y}, −m

_{z}), (0, 1/2, 1/2 | −m

_{x}, m

_{y}, −m

_{z}) and (1/2, 0, 1/2 | −m

_{x}, −m

_{y}, m

_{z}). This magnetic group corresponds to antiferromagnetic ordering. This is shown in Figure 6.

_{x}, m

_{y}, m

_{z}}, {1/2, 1/2, 0 | m

_{x}, −m

_{y}, −m

_{z}}, {0, 1/2, 1/2 | −m

_{z}, m

_{y}, −m

_{z}}, {1/2, 0, 1/2 | −m

_{z}, −m

_{y}, m

_{z}}, {0, 0, 0 | −m

_{x}, −m

_{y}, −m

_{z}}, {1/2, 1/2, 0 | −m

_{x}, m

_{y}, m

_{z}}, {0, 1/2, 1/2 | m

_{z}, −m

_{y}, m

_{z}} and {1/2, 0, 1/2 | m

_{z}, m

_{y}, −m

_{z}}. For example, the expressions of {0, 0, 0 | m

_{x}, m

_{y}, m

_{z}} and {0, 0, 0 | −m

_{x}, −m

_{y}, −m

_{z}} must be same, i.e., m

_{x}= −m

_{x}, m

_{y}= −m

_{y}and m

_{z}= −m

_{z}. This is also valid for another expression. This means that all magnetic moments must be zero. With this magnetic space group, it is impossible to describe an antiferromagnetic ordering. In Figure 8, the possible spin arrangements are shown.

_{x}, m

_{y}, m

_{z}}, {1/2, 0, 1/2 | −m

_{x}, −m

_{y}, m

_{z}}, {0, 1/2, 1/2 | m

_{x}, −m

_{y}, m

_{z}}, {1/2, 1/2, 0 | −m

_{z}, m

_{y}, m

_{z}}, {0, 0, 0 | m

_{x}, m

_{y}, m

_{z}}, {1/2, 0, 1/2 | −m

_{x}, −m

_{y}, m

_{z}}, {0, 1/2, 1/2 | m

_{x}, −m

_{y}, m

_{z}} and {1/2, 1/2, 0 | −m

_{x}, m

_{y}, m

_{z}}. Among a total eight expressions, only four expressions (namely {0, 0, 0 | m

_{x}, m

_{y}, m

_{z}}, {1/2, 0, 1/2 | −mx, −m

_{y}, m

_{z}}, {0, 1/2, 1/2 | m

_{x}, −m

_{y}, m

_{z}} and {1/2, 1/2, 0 | −m

_{x}, m

_{y}, m

_{z}}) are unique. Based on this magnetic space group, in the xy-plane, an antiferromagnetic ordering is allowed and along the c-axis, a ferromagnetic ordering is possible. In Figure 9, the spin arrangements of magnetic space group Pb’c’a are shown.

_{x}, m

_{y}, m

_{z}}, {1/2, 1/2, 0 | m

_{x}, m

_{y}, −m

_{z}}, {0, 1/2, 1/2 | −m

_{x}, m

_{y}, −m

_{z}}, {1/2, 0, 1/2 | −m

_{x}, −m

_{y}, m

_{z}}, {0, 0, 0 | −m

_{x}, −m

_{y}, −m

_{z}}, {1/2, 1/2, 0 | −m

_{x}, m

_{y}, m

_{z}}, {0, 1/2, 1/2 | m

_{x}, −m

_{y}, m

_{z}} and {1/2, 0, 1/2 | m

_{x}, m

_{y}, −m

_{z}}. For example, the expression {0, 0, 0 | m

_{x}, m

_{y}, m

_{z}} must be equal to {0, 0, 0 | −m

_{x}, m

_{y}, −m

_{z}} and this means that m

_{x}= −m

_{x}, m

_{y}= −m

_{y}and m

_{z}= −m

_{z}. To satisfy these conditions, m

_{x}= m

_{y}= m

_{z}= 0, i.e., no magnetic ordering is possible if an atom occupies a 4a position. In Figure 10, the magnetic space group of Pb’c’a’ is shown. Among the above five magnetic space groups derived from the crystallographic space group Pbca, the magnetic ordering is only possible in the two magnetic space groups Pbca and Pb’c’a. Compared to the parent crystallographic space group Pbca, two magnetic space groups Pbca and Pb’c’a show the same translational symmetry, i.e., two magnetic space groups have same lattice parameters of the parent crystallographic space group Pbca. This means that the propagation vector must be (0 0 0). According to the previous research using magnetic susceptibility measurements [6], antiferromagnetic ordering is observed along the c-axis. However, as already discussed in the text, in the case of the magnetic space group Pb’c’a, along the c-axis, only ferromagnetic ordering is possible. Thus, the magnetic space group Pb’c’a can be ruled out and the only possible magnetic space group is Pbca.

## 4. Conclusions

^{2+}in the crystal structure, after our reactor is restarted after its long shut-down period.

## Author Contributions

## Funding

## Conflicts of Interest

## References

- Kagan, C.R.; Mitzi, D.B.; Dimitrakopoulos, C.D. Organic-Inorganic hybrid materials as semiconducting channels in thin-film field-effect transistors. Science
**1999**, 286, 945–947. [Google Scholar] [CrossRef] - Mitzi, D.B. Thin-film deposition of organic-inorganic hybrid materials. Chem. Comm.
**2001**, 13, 3283–3298. [Google Scholar] [CrossRef] - Kundys, B. Multiferroicity and hydrogen ordering in (C2H5NH3)2CuCl4 featuring dominant ferromagnetic interactions. Phys. Rev. B
**2010**, 81, 224434. [Google Scholar] [CrossRef] [Green Version] - Lines, M.E. Magnetism in two dimensions. J. Appl. Phys.
**1969**, 40, 1352–1358. [Google Scholar] [CrossRef] - Oh, I.H.; Kim, D.; Huh, Y.D.; Park, Y.; Park, J.M.S.; Park, S.H. Bis(2-phenylethylammonium)tetrachloridocobaltate(II). Acta Cryst. E
**2011**, 67, m522–m523. [Google Scholar] [CrossRef] [PubMed] - Park, S.H.; Oh, I.H.; Park, S.; Park, Y.; Kim, J.H.; Huh, Y.D. Canted antiferromagnetism and spin reorientation transition in layered inorganic-organic perovskite (C6H5CH2CH2NH3)2MnCl4. Dalton Trans.
**2012**, 41, 1237–1242. [Google Scholar] [CrossRef] [PubMed] - Polyakov, A.O.; Arkenbout, A.H.; Baas, J.; Blake, G.R.; Meetsma, A.; Caretta, A.; van Loosdrecht, P.H.M.; Palstra, T.T.M. Coexisting ferromagnetic and ferroelectric order in a CuCl4-based organic inorganic hybrid. Chem. Mater.
**2012**, 24, 133–139. [Google Scholar] [CrossRef] [Green Version] - Kim, K.Y.; Park, G.; Cho, J.; Kim, J.; Kim, J.-S.; Jung, J.; Park, K.; You, C.-Y.; Oh, I.H. Intrinsic magnetic order of chemically exfoliated 2D Ruddlesden-Popper organic-inorganic halide perovskite ultrathin films. Small
**2020**. accepted. [Google Scholar] [CrossRef] - Izyumov, Y.A.; Ozero, R.P. Magnetic Neutron Diffraction; Plenum Press: New York, NY, USA, 1970; pp. 30–31. [Google Scholar]
- Aroyo, M.I.; Magnetic Point Groups. Role of Magnetic Symmetry in the Description and Determination of Magnetic Structures. In Proceedings of the IUCr Congress Satellite Workshop, Hamilton, ON, Canada, 14–16 August 2014. [Google Scholar]
- Hahn, T. (Ed.) International Tables for Crystallography, 5th ed.; Space-Group Symmetry; Kluwer Academic Publishers: Dordrecht, The Netherlands, 2002; Volume A. [Google Scholar]
- Park, G.; Oh, I.H.; Park, J.M.S.; Park, S.H.; Hong, C.S.; Lee, K.S. Investigation of magnetic phase transition on the layered inorganic-organic hybrid perovskites (C6H5CH2CH2NH3)2MnCl4 by single-crystal neutron diffraction. Phys. B Phys. Condens. Matter
**2018**, 561, 89–93. [Google Scholar] [CrossRef] - Oh, I.H.; Kim, J.E.; Koo, J.; Park, J.M.S. Refinement of cesium diaquatrichloromanganate(II), CsMnCl
_{2}.2H(H2O) by neutron diffraction, Cl3CsH4MnO2. Z. Kristallogr. NCS**2014**, 229, 265–266. [Google Scholar] - Litvin, D.B.; Magnetic Group Tables. 1-, 2- and 3-Dimensional Magnetic Subperiodic Groups and Magnetic Space Groups. Part 1. Introduction; International Union of Crystallography: Chester, UK, 2013; Available online: www.iucr.org/publ/978-0-9553602-2-0 (accessed on 30 November 2020).
- Litvin, D.B.; Magnetic Group Tables. 1-, 2- and 3-Dimensional Magnetic Subperiodic Groups and Magnetic Space Groups. Part 2. Tables of Magnetic Groups; International Union of Crystallography: Chester, UK, 2013; Available online: www.iucr.org/publ/978-0-9553602-2-0 (accessed on 30 November 2020).

**Figure 1.**Time reversal effect on the axial vector. The current loop changes its sense under a time-reversal operation.

**Figure 4.**Several selected magnetic peaks below the magnetic phase transition temperature of Mn-PEA [12]. (

**a**) (−1 0 0); (

**b**) (3 −3 0); (

**c**) (−1 −2 0).

**Figure 5.**Temperature dependence of forbidden magnetic peak (−1 0 0) and nuclear peak (2 0 0) of Mn-PEA from neutron single-crystal diffraction [12].

**Figure 9.**Possible spin arrangement in the magnetic space group Pb’c’a. In this configuration, the spin directions of (0 0 0) and (1/2 1/2 0) are different. Thus in the xy-plane, antiferromagnetic ordering is possible. This is valid for (0 1/2 1/2) and (1/2 0 1/2). Along the c-axis, only ferromagnetic ordering is possible.

**Table 1.**Magnetic point groups M

_{m’m’m’}, M

_{mmm’}and M

_{m’m’2}. In (x, y, z) form, the integer +1 means a proper rotation and −1 means an improper rotation. m

_{x}, m

_{y}and m

_{z}denote the magnetic components along each axis.

Symbol (Mm’m’m’) | (x, y, z) Form | Symbol (Mmmm’) | (x, y, z) Form | Symbol (Mm’m’2) | (x, y, z) Form |
---|---|---|---|---|---|

1 | x, y, z, +1 | 1 | x, y, z, +1 | 1 | x, y, z, +1 |

m_{x}, m_{y}, m_{z} | m_{x}, m_{y}, m_{z} | m_{x}, m_{y}, m_{z} | |||

2_{x} | x, −y, −z, +1 | 2_{x} | x, −y, −z, +1 | 2_{z} | −x, −y, z, +1 |

m_{x}, −m_{y}, −m_{z} | m_{x}, −m_{y}, −m_{z} | −m_{x}, −m_{y}, m_{z} | |||

2_{y} | x, −y, −z, +1 | m_{y} | x, −y, z, +1 | −1 | −x, −y, −z, +1 |

m_{x}, −m_{y}, −m_{z} | −m_{x}, m_{y}, −m_{z} | m_{x}, m_{y}, m_{z} | |||

2_{z} | −x, −y, z, +1 | m_{z} | x, y, −z, +1 | m_{z} | x, y, −z, +1 |

−m_{x}, −m_{y}, m_{z} | −m_{x}, −m_{y}, m_{z} | −m_{x}, −m_{y}, m_{z} | |||

−1′ | −x, −y, −z, −1 | 2_{y’} | −x, −y, −z, −1 | 2_{x’} | x, −y, −z, −1 |

−m_{x}, −m_{y}, -m_{z} | −m_{x}, −m_{y}, −m_{z} | −m_{x}, m_{y}, m_{z} | |||

m_{x’} | −x, y, z, −1 | 2_{z’} | −x, −y, z, −1 | 2_{y’} | −x, y, −z, −1 |

−m_{x}, m_{y}, m_{z} | m_{x}, m_{y}, −m_{z} | m_{x}, −m_{y}, m_{z} | |||

m_{y’} | x, −y, z, −1 | −1′ | −x, −y, −z, −1 | m_{z’} | −x, y, z, −1 |

m_{x}, −m_{y}, m_{z} | −m_{x}, −m_{y}, −m_{z} | −m_{x}, m_{y}, m_{z} | |||

m_{z’} | x, y, −z, −1 | m_{x’} | −x, y, z, −1 | m_{y’} | x, −y, z, −1 |

m_{x}, my, −m_{z} | −m_{x}, m_{y}, m_{z} | m_{x}, −m_{y}, m_{z} |

**Table 2.**Magnetic space groups Pbca, Pbca1′, Pb’ca, Pb’c’a and Pb’c’a’. The integer +1 means a proper rotation and −1 means an improper rotation. m

_{x}, m

_{y}and m

_{z}mean the magnetic component along each axis [15].

Pbca | Pbca1′ | Pb’ca | Pb’c’a | Pb’c’a’ |
---|---|---|---|---|

x, y, z, +1 | x, y, z, +1 | x, y, z, +1 | x, y, z, +1 | x, y, z, +1 |

m_{x}, m_{y}, m_{z} | 0, 0, 0 | m_{x}, m_{y}, m_{z} | m_{x}, m_{y}, m_{z} | m_{x}, m_{y}, m_{z} |

x+1/2, −y+1/2, −z, +1 | x+1/2, −y+1/2, −z, +1 | x+1/2, −y+1/2, −z, +1 | −x+1/2, −y, z+1/2, +1 | x+1/2, −y+1/2,−z, +1 |

m_{x}, −m_{y}, −m_{z} | 0, 0, 0 | m_{x}, −m_{y}, −m_{z} | −m_{x}, −m_{y}, m_{z} | m_{x}, −m_{y}, −m_{z} |

−x, y+1/2, −z+1/2, +1 | −x, y+1/2, −z+1/2, +1 | x, −y+1/2, z+1/2, +1 | −x, −y, −z, +1 | −x, y+1/2, −z+1/2, +1 |

−m_{x}, m_{y}, −m_{z} | 0, 0, 0 | −m_{x}, m_{y}, −m_{z} | m_{x}, m_{y}, m_{z} | −m_{x}, m_{y}, −m_{z} |

−x+1/2, −y, z+1/2, +1 | −x+1/2, −y, z+1/2, +1 | x+1/2, y, −z+1/2, +1 | x+1/2, y, −z+1/2, +1 | −x+1/2, −y, z+1/2, +1 |

−m_{x}, −m_{y}, m_{z} | 0, 0, 0 | −m_{x}, −m_{y}, m_{z} | −m_{x}, −m_{y}, m_{z} | −m_{x}, −m_{y}, m_{z} |

−x, −y, −z, +1 | −x, −y, −z, +1 | −x, y+1/2, −z+1/2, −1 | x+1/2, −y+1/2, −z, −1 | −x, −y, −z, −1 |

m_{x}, m_{y}, m_{z} | 0, 0, 0 | m_{x}, −m_{y}, m_{z} | −m_{x}, m_{y}, m_{z} | −m_{x}, −m_{y}, −m_{z} |

−x+1/2, y+1/2, z, +1 | −x+1/2, y+1/2, z, +1 | −x+1/2, −y, z+1/2, −1 | −x, y+1/2, −z+1/2, −1 | −x+1/2, y+1/2,z, −1 |

m_{x}, −m_{y}, −m_{z} | 0, 0, 0 | m_{x}, m_{y}, −m_{z} | m_{x}, −m_{y}, m_{z} | −m_{x}, m_{y}, m_{z} |

x, −y+1/2, z+1/2, +1 | x, −y+1/2, z+1/2, +1 | −x, −y, −z, −1 | −x+1/2, y+1/2, z, −1 | x, −y+1/2, z+1/2, −1 |

−m_{x}, m_{y}, −m_{z} | 0, 0, 0 | −m_{x}, −m_{y}, −m_{z} | −m_{x}, m_{y}, m_{z} | m_{x}, −m_{y}, m_{z} |

x+1/2, y, −z+1/2, +1 | x+1/2, y, −z+1/2, +1 | −x+1/2, y+1/2, z, −1 | x, −y+1/2, z+1/2, −1 | x+1/2, y, −z+1/2, −1 |

−m_{x}, −m_{y}, m_{z} | 0, 0, 0 | −m_{x}, m_{y}, m_{z} | m_{x}, −m_{y}, m_{z} | m_{x}, m_{y}, −m_{z} |

Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. |

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).

## Share and Cite

**MDPI and ACS Style**

Park, G.; Oh, I.-H.; Park, J.M.S.; Hahn, S.; Park, S.-H.
Magnetic Structure of Inorganic–Organic Hybrid (C_{6}H_{5}CH_{2}CH_{2}NH_{3})_{2}MnCl_{4} Using Magnetic Space Group Concept. *Symmetry* **2020**, *12*, 1980.
https://doi.org/10.3390/sym12121980

**AMA Style**

Park G, Oh I-H, Park JMS, Hahn S, Park S-H.
Magnetic Structure of Inorganic–Organic Hybrid (C_{6}H_{5}CH_{2}CH_{2}NH_{3})_{2}MnCl_{4} Using Magnetic Space Group Concept. *Symmetry*. 2020; 12(12):1980.
https://doi.org/10.3390/sym12121980

**Chicago/Turabian Style**

Park, Garam, In-Hwan Oh, J. M. Sungil Park, Seungsoo Hahn, and Seong-Hun Park.
2020. "Magnetic Structure of Inorganic–Organic Hybrid (C_{6}H_{5}CH_{2}CH_{2}NH_{3})_{2}MnCl_{4} Using Magnetic Space Group Concept" *Symmetry* 12, no. 12: 1980.
https://doi.org/10.3390/sym12121980