Photomagnetic molecular and extended network Langmuir–Blodgett films based on cyanide bridged molybdenum–copper complexes

Abstract

Two types of cyanide bridged molybdenum-copper photomagnetic films have been obtained: the first one is based on a molecular [MoCu 6 ] complex, the other being a two-dimensional [MoCu 2 ] coordination network. Both systems employ surfactant functionalized ligands and films were deposited on Melinex substrates using the Langmuir-Blodgett technique. All systems, including monolayer films, showed full retention of the intrinsic photomagnetic properties known for analogous solids as demonstrated by EPR spectroscopy.

Direct Evidence of a Photoinduced Electron Transfer in Diluted “Molybdenum‐Copper” Molecular Compounds

“…[1][2][3][4][5][6][7][8][9][10] Most of the compounds display a reversible photoinduced magnetic bistability that has been developed into various forms: three-dimensional networks, [11][12][13] molecular complexes, [14][15][16][17][18] high nuclearity clusters, [19,20] chains, [21,22] nanoparticles [23,24] and films. [25][26][27] In addition, the integration of Mo-Cu complexes viewed as magnetic switches into sophisticated architectures [28,29] has been performed with success as well as their transformation into promising materials with various properties. [30,31] However, a debate has emerged concerning the mechanism that might justify the related photomagnetic properties: loss of a ligand, [32] spin transition or electron transfer, the question remains open.…”

“…Molybdenum‐copper complexes have attracted great attention over the past decade due to the interesting photomagnetic phenomena that have been reported for these systems . Most of the compounds display a reversible photoinduced magnetic bistability that has been developed into various forms: three‐dimensional networks, molecular complexes, high nuclearity clusters,, chains,, nanoparticles, and films . In addition, the integration of Mo‐Cu complexes viewed as magnetic switches into sophisticated architectures, has been performed with success as well as their transformation into promising materials with various properties , .…”

Chiral Photomagnets Based on Copper(II) complexes of 1,2-Diaminocyclohexane and Octacyanidomolybdate(IV) Ions

“…Prompted by these discoveries, we continue our intensive research on photoinduced magnetization in heterometallic systems based on photoactive [Mo IV (CN) 8 ] 4– and [W IV (CN) 8 ] 4– ions. The related Cu II –Mo IV networks were proved to reveal a photoinduced singlet–triplet spin transition in [Mo IV (CN) 8 ] 4– ions and concurrent MMCT transitions, − the last one also supported by ab initio calculations. Thus, it is expected that for the specific coordination geometries of these octacyanidometalates both processes, spin transition and charge transfer, could be induced by light irradiation. , …”

Electrospray ionization: an efficient approach to deposit polymetallic molecular switches onto gold surfaces

“…12 More sophisticated methods have to be used to target (sub)monolayer of mono/polymetallic magnetic switches on surfaces. For example, polymetallic photomagnetic charge transfer complexes were deposited onto surfaces using the Langmuir-Blodgett method, 13 while selfassembled monolayers of valence tautomeric complexes could be obtained by functionalizing a ligand with an anchoring group. 14 Overall, these examples of successful monolayer deposition remain scarce although the properties of the polymetallic complexes are very attractive.…”

“…In these cubic complexes, the central caesium ion occupies the cubic cavity and interacts with the twelve cyanide edges, conferring a remarkable stability to the polymetallic complex. It was not possible to obtain single crystal suitable for X-ray diffraction, however the actual molecule composition was checked by elemental analysis, 1 H, 13 C (1D and 2D) and 133 Cs NMR (details in ESI). For example, the 133 Cs NMR spectrum shows a unique peak corresponding to the inserted alkali ion.…”