TY - JOUR

T1 - Red phosphorescent octahedral complexes of manganese(II) based on the simplest monodentate phosphine oxides

AU - Taigina, M. D.

AU - Nafikov, M. D.

AU - Kolybalov, D. S.

AU - Berezin, A. S.

AU - Pervukhina, N. V.

AU - Naumov, D. Yu

AU - Syrokvashin, M. M.

AU - Vinogradova, K. A.

N1 - The work was funded by Russian Science Foundation (grant № 25-73-10218). The authors are grateful to Alexandra A. Shapovalova for her help with IR spectra and to Irina V. Yushina for recording the diffuse reflectance spectra and to Maria O. Matveeva for recording X-ray powder diffraction patterns and to Konstantin D. Muyanov for the thermal gravimetric analysis. The authors would also like to thank the Microanalysis Laboratory of Vorozhtsov Novosibirsk Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences for elemental analysis. The authors thank XRD Facility of NIIC SB RAS and personally to Dr. Taisiya S. Sukhikh and Danil V. Kochelakov for the single-crystal X-ray diffraction data collection. The powder XRD analysis (STOE STADI MP powder X-ray diffractometer) was carried out with equipment of the Chair of the Solid State Chemistry at Novosibirsk State University.

PY - 2026/9

Y1 - 2026/9

N2 - Six mononuclear high-spin luminescent manganese(II) complexes based on diphenylphosphine oxide (OPPh2H) and triphenylphosphine oxide (OPPh3) have been synthesized and characterized. Complexes [Mn(OPPh2H)6](BF4)2 and [Mn(OPPh2H)6](ClO4)2 have been prepared by a reaction between MnХ2‧nH2O (X = BF4¯, ClO4¯) and OPPh2H in a 1:6 M ratio in MeCN/EtOH solutions. According to the single-crystal X-ray analysis, both complexes have the same ionic structure consisting of slightly distorted octahedral cations [Mn(OPPh2H)6]2+ and outer shell anions. A reaction of salts MnХ2‧nH2O with the more sterically crowded ligand OPPh3 at molar ratios of 1:2, 1:4 or 1:6 leads to the formation of complexes with the composition [Mn(OPPh3)4(H2O)(X)]X (X = BF4¯, ClO4¯). The single-crystal X-ray analysis reveals that these compounds are isostructural and have an ionic structure consisting of an octahedral complex cation, [Mn(OPPh3)4(H2O)(X)]+, and an uncoordinated anion X¯. The coordination polyhedron around the Mn atom in the complex cation can be described as an almost ideal octahedron, which is formed by four O atoms from four monodentate coordinated OPPh3 molecules that occupy equatorial positions, one aqua ligand and an X¯ anion are located axially. The complexes exhibit red phosphorescence in the 600–650 nm range in the solid state at room temperature. The emission bands originate from the 4T1 → 6А1 transition of the manganese center in the octahedral field. The emission quantum yield of [Mn(OPPh2H)6](BF4)2 is 9%. The chromaticity coordinates (CIE 1931) of [Mn(OPPh3)4(H2O)(ClO4)]ClO4 are (0.6721, 0.3246), which are close to the red color for the OLED BT.2020 standard.

AB - Six mononuclear high-spin luminescent manganese(II) complexes based on diphenylphosphine oxide (OPPh2H) and triphenylphosphine oxide (OPPh3) have been synthesized and characterized. Complexes [Mn(OPPh2H)6](BF4)2 and [Mn(OPPh2H)6](ClO4)2 have been prepared by a reaction between MnХ2‧nH2O (X = BF4¯, ClO4¯) and OPPh2H in a 1:6 M ratio in MeCN/EtOH solutions. According to the single-crystal X-ray analysis, both complexes have the same ionic structure consisting of slightly distorted octahedral cations [Mn(OPPh2H)6]2+ and outer shell anions. A reaction of salts MnХ2‧nH2O with the more sterically crowded ligand OPPh3 at molar ratios of 1:2, 1:4 or 1:6 leads to the formation of complexes with the composition [Mn(OPPh3)4(H2O)(X)]X (X = BF4¯, ClO4¯). The single-crystal X-ray analysis reveals that these compounds are isostructural and have an ionic structure consisting of an octahedral complex cation, [Mn(OPPh3)4(H2O)(X)]+, and an uncoordinated anion X¯. The coordination polyhedron around the Mn atom in the complex cation can be described as an almost ideal octahedron, which is formed by four O atoms from four monodentate coordinated OPPh3 molecules that occupy equatorial positions, one aqua ligand and an X¯ anion are located axially. The complexes exhibit red phosphorescence in the 600–650 nm range in the solid state at room temperature. The emission bands originate from the 4T1 → 6А1 transition of the manganese center in the octahedral field. The emission quantum yield of [Mn(OPPh2H)6](BF4)2 is 9%. The chromaticity coordinates (CIE 1931) of [Mn(OPPh3)4(H2O)(ClO4)]ClO4 are (0.6721, 0.3246), which are close to the red color for the OLED BT.2020 standard.

KW - Crystal structure

KW - Diphenylphosphine oxide

KW - Manganese(II) complexes

KW - Phosphorescence

KW - Solid-state red emission

KW - Triphenylphosphine oxide

UR - https://www.scopus.com/pages/publications/105042118661

UR - https://www.mendeley.com/catalogue/a3346439-7d3c-3885-aac2-92aea9f8da2b/

U2 - 10.1016/j.inoche.2026.116997

DO - 10.1016/j.inoche.2026.116997

M3 - Article

VL - 191

JO - Inorganic Chemistry Communication

JF - Inorganic Chemistry Communication

SN - 1387-7003

IS - Part 1

M1 - 116997

ER -