Electronic Structure of Manganese Phthalocyanine Modified via Potassium Intercalation: a Comprehensive Experimental Study

TL;DR

This study provides a comprehensive experimental analysis of how potassium intercalation alters the electronic structure of manganese phthalocyanine, revealing shifts in energy levels, increased spin states, and strong orbital hybridization.

Contribution

It offers new experimental insights into the electronic configuration changes in K-doped MnPc, clarifying controversies and detailing the hybridization and spin state evolution.

Findings

Fermi level shifts towards LUMO with K doping

Increase in Mn spin state upon intercalation

Strong hybridization between Mn 3d and N 2p states

Abstract

Potassium (K) intercalated manganese phthalocyanine (MnPc) reveals vast changes of its electronic states close to the Fermi level. However, theoretical studies are controversial regarding the electronic configuration. Here, MnPc doped with K was studied by ultraviolet, X-ray, and inverse photoemission, as well as near edge X-ray absorption fine structure spectroscopy. Upon K intercalation the Fermi level shifts toward the lowest unoccupied molecular orbital filling it up with donated electrons with the appearance of an additional feature in the energy region of the occupied states. The electronic bands are pinned 0.5 eV above and 0.4 eV below the Fermi level. The branching ratio of the Mn L3 and L2 edges indicate an increase of the spin state. Moreover, the evolution of the Mn L and N K edges reveals strong hybridization between Mn 3d and N 2p states of MnPc and sheds light on the electron occupation in the ground and n-doped configurations.