![\"Single](\"https:\/\/www.newsbeep.com\/us\/wp-content\/uploads\/2025\/11\/single-organic-molecul.jpg\" "\\"Illustration")
<\/p>\n\n\t\t\t\t\t\t\t\t\t\t\tby Li Xiangyang; Zhao Weiwei, Hefei Institutes of Physical Science, Chinese Academy of Sciences\t\t\t\t\t\t\t\t\t<\/p>\n
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Illustration of a molecular Kondo-box singlet formed by large orbital overlap between symmetry-matched d\u03c0 and \u03c0 orbitals in an atomic\/molecular system on a metal surface. Credit: Li Xiangyang<\/p>\n
A research group led by Prof. Li Xiangyang from the Hefei Institutes of Physical Science of the Chinese Academy of Sciences, has made a new discovery: a single organic molecule can induce the Kondo effect in a magnetic atom, challenging the long-standing belief that this quantum phenomenon requires a vast sea of metallic electrons.<\/p>\n
The research results were published<\/a> in Physical Review Letters.<\/p>\n The Kondo effect is a quantum many-body phenomenon where conduction electrons in a metal collectively screen the magnetic moment of a localized impurity atom. It has been helping to explain strongly correlated electron behavior and inspiring advances in nanoscience, molecular electronics<\/a>, and quantum information research.<\/p>\n Traditionally, it was believed that this effect could only emerge in systems with a large reservoir of metallic electrons, making the new results especially striking.<\/p>\n In this study, the researchers demonstrate that cobalt<\/a> phthalocyanine (CoPc) molecules deposited on a metallic substrate can act as an itinerant-like electron reservoir to screen the spin state of a cobalt atom, creating the first “molecular Kondo box.”<\/p>\n First-principles calculations and experimental validation revealed that in the Co\u2013CoPc\/Au(111) system, the \u03c0-electron states of the CoPc molecule hybridize with conduction electrons of the Au(111) substrate. This hybridization<\/a> allows the molecule’s own \u03c0-electrons to exhibit itinerant-like behavior.<\/p>\n These \u03c0-orbitals strongly overlap with the symmetrically matched d\u03c0 orbitals of the cobalt atom, suppressing competing screening from the metallic substrate and enabling the formation of a Kondo singlet at the molecular scale.<\/p>\n Remarkably, the corresponding Kondo temperature can be precisely tuned by controlling the number of cobalt atoms and the overall symmetry of the molecular system.<\/p>\n This discovery not only expands the fundamental understanding of Kondo physics but also demonstrates a new level of stability and tunability in spin states, according to the team.<\/p>\n