Electron Spin Decoherence Dynamics in Magnetic Manganese Hybrid Organic-Inorganic Crystals: The Effect of Lattice Dimensionality

Organic-inorganicmetal hybrids with their tailorable latticedimensionality and intrinsic spin-splitting properties are interestingmaterial platforms for spintronic applications. While the spin decoherenceprocess is extensively studied in lead- and tin-based hybrids, thesesystems generally show short spin decoherence lifetimes, and theircorrelation with the lattice framework is still not well-understood.Herein, we synthesized magnetic manganese hybrid single crystals of(4-fluorobenzylamine)(2)MnCl4, ((R)-3-fluoropyrrolidinium)MnCl3, and (pyrrolidinium)(2)MnCl4, which represent a change in lattice dimensionalityfrom 2D and 1D to 0D, and studied their spin decoherence processesusing continuous-wave electron spin resonance spectroscopy. All manganesehybrids exhibit nanosecond-scale spin decoherence time & tau;(2) dominated by the symmetry-directed spin exchange interactionstrengths of Mn2+-Mn2+ pairs, which ismuch longer than lead- and tin-based metal hybrids. In contrast tothe similar temperature variation laws of & tau;(2) in 2Dand 0D structures, which first increase and gradually drop afterward,the 1D structure presents a monotonous rise of & tau;(2) with the temperatures, indicating the strong correlation of spindecoherence with the lattice rigidity of the inorganic framework.This is also rationalized on the basis that the spin decoherence isgoverned by the competitive contributions from motional narrowing(prolonging the & tau;(2)) and electron-phonon couplinginteraction (shortening the & tau;(2)), both of which arethermally activated, with the difference that the former is more pronouncedin rigid crystalline lattices.

Automated summary

Organic-inorganic metal hybrids are interesting materials for spintronic applications due to their tailorable latticedimensionality and intrinsic spin-splitting properties. In this study, magnetic manganese hybrid single crystals with different lattice dimensionality were synthesized and their spin decoherence processes were studied. The spin decoherence time τ(2) in these hybrids were much longer than lead- and tin-based hybrids, and were influenced by the symmetry-directed spin exchange interaction strengths of Mn2+-Mn2+ pairs. The spin decoherence in these hybrids was found to be strongly correlated with the lattice rigidity of the inorganic framework.