Making Closed-Shell Lead-Pthalocyanine Paramagnetic on Pb(100)

Jan Homberg; Alexander Weismann; Richard Berndt

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arXiv · 2402.08330

Making Closed-Shell Lead-Pthalocyanine Paramagnetic on Pb(100)

Jan Homberg·Alexander Weismann·Richard Berndt

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Abstract

Lead phthalocyanine (PbPc), a non-planar molecule, is studied on Pb(100) using scanning tunneling spectroscopy. A rigid shift of the molecular orbitals is found between molecules with the central Pb ion pointing to (PbPc$\downarrow$) or away (PbPc$\uparrow$) from the substrate and understood from the interaction between the molecules and their image charges. Inside the superconducting energy gap, Yu-Shiba-Rusinov (YSR) resonances are observed for PbPc$\uparrow$ molecules in islands indicating the presence of a magnetic moment. Such bound states are neither present on PbPc$\downarrow$ molecules nor isolated PbPc$\uparrow$ or molecules that lost the Pb ion during deposition (H$_0$Pc). The YSR energies vary depending on the orientation and type of the molecular neighbors. We analyze the role of the out-of-plane dipole moment of PbPc.

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cond-mat.supr-con cond-mat.mes-hall cond-mat.mtrl-sci

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Jan Homberg, Alexander Weismann, Richard Berndt. 2024-02-13. Making Closed-Shell Lead-Pthalocyanine Paramagnetic on Pb(100). https://arxiv.org/abs/2402.08330

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