TY - JOUR

T1 - Crystal and Electronic Structures of New Two Dimensional 3-NH3-PyPbX4 Haloplumbate Materials

AU - Селиванов, Никита Иванович

AU - Кеворкянц, Руслан Эдуардович

AU - Емелин, Алексей Владимирович

AU - Стомпос, Константинос

PY - 2023

Y1 - 2023

N2 - In this study, we explored both the crystal and electronic structures of new synthesized materials 3-NH 3-PyPbX 4 (X = Br, I). Both compounds are isostructural, and they crystallize in the monoclinic space group P2 1/ c, with four formula units in the unit cell. According to the analysis of their electronic structures, both compounds are direct semiconductors with direct transitions between valence and conduction bands occurring at the k-points A, Z, and at about half of the distance between the k-points D/D1 and D1/E. An inspection of DOS reveals that, in both perovskites, the highest energy VBs are comprised mainly of electronic states of halogen anions, while the lowest states in the conduction band originate from lead orbitals. In addition, there are two flat bands composed of electronic states of carbon and nitrogen originating from the organic subsystems and presumably corresponding to the π* orbitals of 3-NH 3-C 5H 6N cations. Both materials demonstrate a broad luminescence emission. Two mechanisms of the radiative relaxation based on either self-trapped excitons or on charge transfers between inorganic and organic subsystems are discussed.

AB - In this study, we explored both the crystal and electronic structures of new synthesized materials 3-NH 3-PyPbX 4 (X = Br, I). Both compounds are isostructural, and they crystallize in the monoclinic space group P2 1/ c, with four formula units in the unit cell. According to the analysis of their electronic structures, both compounds are direct semiconductors with direct transitions between valence and conduction bands occurring at the k-points A, Z, and at about half of the distance between the k-points D/D1 and D1/E. An inspection of DOS reveals that, in both perovskites, the highest energy VBs are comprised mainly of electronic states of halogen anions, while the lowest states in the conduction band originate from lead orbitals. In addition, there are two flat bands composed of electronic states of carbon and nitrogen originating from the organic subsystems and presumably corresponding to the π* orbitals of 3-NH 3-C 5H 6N cations. Both materials demonstrate a broad luminescence emission. Two mechanisms of the radiative relaxation based on either self-trapped excitons or on charge transfers between inorganic and organic subsystems are discussed.

KW - absorption spectra

KW - charge transfer

KW - crystal structure

KW - electronic structure

KW - exciton

KW - hybrid haloplumpates

KW - luminescence spectra

KW - photoexcitation

UR - https://www.mendeley.com/catalogue/9b5b42c4-7174-3f91-89b2-7d1641f77334/

U2 - 10.3390/ma16010353

DO - 10.3390/ma16010353

M3 - Article

C2 - 36614691

VL - 16

JO - Materials

JF - Materials

SN - 1996-1944

IS - 1

M1 - 353

ER -