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The structural and magnetic properties of F16CuPc thin films and powder, including x-ray diffraction (XRD), superconducting quantum interference device (SQUID) magnetometry, and theoretical modelling of exchange interactions are reported. Analysis of XRD from films, with thickness ranging between 100 and 160 nm, deposited onto Kapton and a perylene-3,4,9,10-tetracarboxylic-3,4,9,10-dianhydride (PTCDA) interlayer shows that the stacking angle (defined in the text) of the film is independent of the thickness, but that the texture is modified by both film thickness and substrate chemistry. The SQUID measurements suggest that all samples are paramagnetic, a result that is confirmed by our theoretical modelling including density functional theory calculations of one-dimensional molecular chains and Green's function perturbation theory calculations for a molecular dimer. By investigating theoretically a range of different geometries, we predict that the maximum possible exchange interaction between F16CuPc molecules is twice as large as that in unfluorinated copper-phthalocyanine (CuPc). This difference arises from the smaller intermolecular spacing in F16CuPc. Our density functional theory calculation for isolated F16CuPc molecule also shows that the energy levels of Kohn-Sham orbitals are rigidly shifted similar to 1 eV lower in F16CuPc compared to CuPc without a significant modification of the intramolecular spin physics, and that therefore the two molecules provide a suitable platform for independently varying magnetism and charge transport.

This paper is concerned with the propagation of Lamb waves in double-layered nanoplates and a nonlocal continuum model is presented. Each layer of the double-layered nanoplates is coupled through the van der Waals interaction. The equations of wave motion are derived and dispersion relations are obtained. The present model predicts some notable features of the dispersion relations in double-layered nanoplates, in comparison with Lamb waves in classic plates in vacuo. By considering the van der Waals interaction, some modes appear in pairs at the same frequency, their phase velocities are very close at a given frequency. Some modes only propagate in a very narrow frequency band and may disappear above certain frequencies. The small-scale has significant influence on the propagation characteristics of Lamb waves. Larger values of the scale coefficient result in lower escape frequencies and phase velocities of Lamb waves.