Péter Matus

Optimized unconventional superconductivity in a molecular Jahn-Teller metal.

A superconductivity dome is created by the electronic structure of the molecular building block of an unconventional superconductor. Understanding the relationship between the superconducting, the neighboring insulating, and the normal metallic state above Tc is a major challenge for all unconventional superconductors. The molecular A3C60 fulleride superconductors have a parent antiferromagnetic insulator in common with the atom-based cuprates, but here, the C603– electronic structure controls the geometry and spin state of the structural building unit via the on-molecule Jahn-Teller effect. We identify the Jahn-Teller metal as a fluctuating microscopically heterogeneous coexistence of both localized Jahn-Teller–active and itinerant electrons that connects the insulating and superconducting states of fullerides. The balance between these molecular and extended lattice features of the electrons at the Fermi level gives a dome-shaped variation of Tc with interfulleride separation, demonstrating molecular electronic structure control of superconductivity.

Structural disorder and local order of hNopp140.

Human nucleolar phosphoprotein p140 (hNopp 140) is a highly phosphorylated protein inhibitor of casein kinase 2 (CK2). As in the case of many kinase-inhibitor systems, the inhibitor has been described to belong to the family of intrinsically disordered proteins (IDPs), which often utilize transient structural elements to bind their cognate enzyme. Here we investigated the structural status of this protein both to provide distinct lines of evidence for its disorder and to point out its transient structure potentially involved in interactions and also its tendency to aggregate. Structural disorder of hNopp140 is apparent by its anomalous electrophoretic mobility, protease sensitivity, heat stability, hydrodynamic behavior on size-exclusion chromatography, (1)H NMR spectrum and differential scanning calorimetry scan. hNopp140 has a significant tendency to aggregate and the change of its circular dichroism spectrum in the presence of 0-80% TFE suggests a tendency to form local helical structures. Wide-line NMR measurements suggest the overall disordered character of the protein. In all, our data suggest that this protein falls into the pre-molten globule state of IDPs, with a significant tendency to become ordered in the presence of its partner as demonstrated in the presence of transcription factor IIB (TFIIB).

Mott localization in the correlated superconductor Cs3C60 resulting from the molecular Jahn-Teller effect

{\mathrm{Na}}_{2}{\mathrm{C}}_{60}

Nanosegregation in Na2C60

is believed to be an electron-hole counterpart of the Mott-Jahn-Teller insulator

Tuning of the Thermoelectric Figure of Merit of CH3NH3MI3 (M═Pb,Sn) Photovoltaic Perovskites

{A}_{4}{\mathrm{C}}_{60}

Dynamic Jahn–Teller effect in the parent insulating state of the molecular superconductor Cs 3 C 60

salts. We present a study of infrared, ESR, NMR spectroscopy, x-ray diffraction, chemical composition and neutron scattering on this compound. Our spectroscopic results at room temperature can be reconciled in a picture of segregated regions of the size

13C NMR investigation of fullerene-cubane C60·C8H8 cocrystals

3\char21{}10\phantom{\rule{0.3em}{0ex}}\mathrm{nm}

1H NMR spectrum and spin‐lattice relaxation in C60 · C8H8

. We observe a significant insulating

NMR evidence of hidden order in the high-temperature phase of (TaSe4)2I

{\mathrm{C}}_{60}