TY - JOUR

T1 - Janus structures of SMoSe and SVSe compositions with low enthalpy and unusual crystal chemistry

AU - Gavryushkin, Pavel

AU - Sagatov, Nursultan

AU - Sukhanova, Ekaterina

AU - Medrish, Inna

AU - Popov, Zakhar

N1 - Janus structures of SMoSe and SVSe compositions with low enthalpy and unusual crystal chemistry / P. Gavryushkin, N. Sagatov, E. Sukhanova [et al.] // Journal of Applied Crystallography. – 2022. – Vol. 55, No. 5. – P. 1324-1335. – DOI 10.1107/s1600576722008202.

PY - 2022

Y1 - 2022

N2 - The recent synthesis of single-layer Janus-type transition metal dichalcogenides (TMDs) raises the question of the existence of other possible 2D structures with an asymmetric out-of-plane structural configuration. In the present work, a theoretical search for new Janus structures having SMoSe and SVSe compositions is performed. A detailed crystal-chemical analysis of the predicted structures is carried out, and it is shown that some of the dynamically stable structures are characterized by crystal-chemical features that are unique among TMDs, including quadruple Mo—Mo bonds and covalent S—S and Se—Se bonds. It is also shown that Mo-bearing TMDs have a tendency to form strong Mo—Mo bonds with chains or isolated dimers of molybdenum atoms, while in the case of vanadium-containing TMDs this feature is not characteristic. Two predicted crystal structures, called 1M-SVSe and 1A′-SMoSe, are especially promising for experimental synthesis and practical applications owing to their dynamical stability and rather low value of enthalpy compared with known structures. The enthalpy of 1M-SVSe is 0.22 eV per formula unit lower than that of 1T-SVSe, while the enthalpy of 1A′-SMoSe is 0.12 eV per formula unit lower than the enthalpy of 1T-SMoSe. The performed topological analysis showed that the predicted structures are unique and do not have analogues in the Inorganic Crystal Structure Database.

AB - The recent synthesis of single-layer Janus-type transition metal dichalcogenides (TMDs) raises the question of the existence of other possible 2D structures with an asymmetric out-of-plane structural configuration. In the present work, a theoretical search for new Janus structures having SMoSe and SVSe compositions is performed. A detailed crystal-chemical analysis of the predicted structures is carried out, and it is shown that some of the dynamically stable structures are characterized by crystal-chemical features that are unique among TMDs, including quadruple Mo—Mo bonds and covalent S—S and Se—Se bonds. It is also shown that Mo-bearing TMDs have a tendency to form strong Mo—Mo bonds with chains or isolated dimers of molybdenum atoms, while in the case of vanadium-containing TMDs this feature is not characteristic. Two predicted crystal structures, called 1M-SVSe and 1A′-SMoSe, are especially promising for experimental synthesis and practical applications owing to their dynamical stability and rather low value of enthalpy compared with known structures. The enthalpy of 1M-SVSe is 0.22 eV per formula unit lower than that of 1T-SVSe, while the enthalpy of 1A′-SMoSe is 0.12 eV per formula unit lower than the enthalpy of 1T-SMoSe. The performed topological analysis showed that the predicted structures are unique and do not have analogues in the Inorganic Crystal Structure Database.

UR - https://www.mendeley.com/catalogue/0eb876a0-f634-3295-a723-9c70cec1d144/

UR - https://www.elibrary.ru/item.asp?id=58729333

U2 - 10.1107/s1600576722008202

DO - 10.1107/s1600576722008202

M3 - Article

VL - 55

SP - 1324

EP - 1335

JO - Journal of Applied Crystallography

JF - Journal of Applied Crystallography

SN - 0021-8898

IS - 5

ER -