Temperature-, Light-, and Soft X-ray-Induced Spin Crossover in a Single Layer of Fe^II-Pyrazolylborate Molecules in Direct Contact with Gold

Abstract

Understanding the properties of spin-crossover molecules in direct contact with metals is crucial for their future integration in electronic and spintronic devices. By X-ray absorption spectroscopy, we investigate the properties of Fe II ((3,5-(CH 3 ) 2 Pz) 3 BH) 2 molecules in the form of monolayer islands on a metallic substrate, namely, Au(111). We demonstrate that the spincrossover transition can be thermally induced from the high spin state to a mixed spin state phase containing one-third of high-spinstate and two-thirds of low-spin-state molecules in agreement with previous work by scanning tunneling microscopy. In addition, at 4.4 K, the spin crossover from the low spin state to the high spin state can also be induced by X-ray and by light excitations.

Influence of Substrate Electronic Properties on the Integrity and Functionality of an Adsorbed Fe(II) Spin-Crossover Compound

“…The conformation and spin-state bistability of spincrossover (SCO) compounds make them attractive for applications [1][2][3][4][5][6] . In that respect, considerable efforts were made to realize thin films of SCO complexes using physical vapor deposition [2][3][4][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24] . These films usually exhibit decent SCO properties.…”

Fragmentation and Distortion of Terpyridine-Based Spin-Crossover Complexes on Au(111)

“…[1][2][3][4][5][6][7][8][9][10][11] Considerable effort has been made to prepare such complexes on surfaces, e. g. for electrical contacting. [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28] To enable physical vapor deposition, which is the most common technique for obtaining high-quality films, compounds with increased thermal stability have been synthesized. However, even for such robust compounds, fragmen-tation issues have been reported.…”

Surface effects on a photochromic spin-crossover iron(ii) molecular switch adsorbed on highly oriented pyrolytic graphite

“…4,5 Their surface organization by sublimation processes onto different substrates, with controlled thickness from micrometres down to sub-monolayer coverage, is crucial for forthcoming technological applications, becoming a highly attractive and flourishing research field during recent years. [6][7][8][9][10][11][12][13][14][15][16][17][18] The retention of switching capability in molecular-inorganic architectures obtained by the regular assembling of SCO molecules on conductive surfaces is a mandatory step towards their integration in hybrid devices. In particular the possibility of obtaining bistable thin films of Fe(II) SCO complexes has been suggested in several recent reports.…”