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Title: Designing molecules with a high-spin (quintet, S = 2) ground state for magnetic and spintronic applications
High-spin ground-state polyradicals are an important platform due to their potential applications in magnetic and spintronic devices. However, a low high-to-low spin energy gap limits the population of the high-spin state, precluding their application at room temperature. Also, design strategies delineating control of the ground electronic state from a closed-shell low-spin to open-shell polyradical character with a high-spin ground state are not well established. Here, we report indacenodinaphthothiophene isomers fused with a 6,6-dicyanofulvene group showing a high-spin quintet ground state. Density functional theory calculations indicate that the syn - and anti -configurations have a closed-shell low-spin singlet ground state. However, the linear -configuration displays a high-spin quintet ground state, with the energy difference between the high-spin quintet to the nearest low-spin excited states calculated to be as large as 0.24 eV (≈5.60 kcal mol −1 ), exhibiting an exclusive population of the high-spin quintet state at room temperature. These molecules are compelling synthetic targets for use in magnetic and spintronic applications.  more » « less
Award ID(s):
1757220
PAR ID:
10417790
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Molecular Systems Design & Engineering
ISSN:
2058-9689
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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