The study of paramagnetic self‐assembled monolayers formed by nitroxide radical (TEMPO)₃O₃P on HOPG

Abstract

aThe studies of (TEMPO) 3 O 3 P molecules (tri-(2,2,6,6-tetramethyl-1-oxyl-4-piperidyl) phosphite) and their monolayers formed on highly oriented pyrolytic graphite (HOPG) are presented. (TEMPO) 3 O 3 P is synthesized from TEMPOL precursor (4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl). We focused on electron paramagnetic resonance (EPR) and scanning tunnelling microscopy (STM) investigations. The EPR experiments demonstrate the paramagnetism of (TEMPO) 3 O 3 P in powdered form and in solution. Furthermore, these paramagnetic properties of (TEMPO) 3 O 3 P are preserved after the deposition on HOPG substrate. The STM studies show that (TEMPO) 3 O 3 P molecules have a strong tendency to form self-assembled monolayers (SAMs). The detailed STM images let us to explore the structure of (TEMPO) 3 O 3 P on HOPG and propose a structural model for the observed SAMs.

The trans–cis isomerization of Ni(η2-TEMPO)2: Interconnections and conformational complexity

“…TEMPO can participate in polymerization and polymerization initiation, [5][6][7][8][9] oxidation of alcohols 10-16 including cellulose and biomaterials, 17 and the molecule possesses a host of other useful properties that make it valuable in electron transfer and spin probe studies. [18][19][20][21][22][23][24] The TEMPO ligand binds readily to metal centers such as nickel and copper, making it a very "green" ligand. [25][26][27][28][29][30] The coordination chemistry of this paramagnetic species has also been shown to afford a variety of bonding motifs.…”