News

Marta Lavrič in George Cordoyiannis sta v sodelovanju s sodelavci z odseka Kompleksne snovi (A. Sterle, N. Sebastian in A. Mertlej) ter skupinami iz Češke akademije znanosti (N. Podoliak, M. Cigl, P. Golub, V. Novotna) in Univerze v Baskiji (A. Erkoreka, J. Martinez-Perdiguero) objavila članek z naslovom »The effect of side chain length on the mesomorphic properties of ferroelectric nematogens (Efekt dolžine stranske verige na mezomorfne lastnosti feroelektričnega nematika)« v reviji Materials Advances.

V članku je bil spremenjen in raziskan predhodno opisan feroelektrični nematogen, ki temelji na molekulski strukturi z dimetilamino zaključno skupino. Raziskan je bil vpliv njegove dolžine na mezomorfne lastnosti v dveh novih homologih s podaljšano stransko verigo. Medtem ko imajo prej opisani homologi neposreden prehod iz izotropne faze (Iso) v feroelektrično nematsko fazo (Nₙ), se pri podaljšani alkilni verigi pojavi ozka vmesna nematska faza (N).

Za nove spojine so bile določene njihove mezomorfne in materialne lastnosti. Feroelektričnost Nₙ faze je bila potrjena z merjenjem polarizacije, SHG signala in permitivnosti.

DOI: 10.1039/d6ma00897f 

Marta Lavrič je v sodelovanju s skupino iz Prage (M. Cigl, N. Podoliak, D. Repček, P. Golub in V. Novotna) objavila članek z naslovom »The effect of fluorine or chlorine substitution on mesomorphic properties of ferroelectric nematic liquid crystals (Efekt fluorove in klorove zamenjave na mezomorfne lastnosti feroelektričnega nematskega tekočega kristala)« v reviji Materials Advances.

Feroelektrična nematska faza (NF) predstavlja zelo zanimivo in hitro razvijajoče se področje raziskav tekočih kristalov, ki združuje fluidnost s feroelektričnostjo. Materiali z NF fazo izkazujejo velike vrednosti polarizacije in izjemne nelinearne optične lastnosti. V članku so bile izdelane izvirne molekulske strukture, tako brez substituentov, kot tudi s halogenskimi substituenti na mestu electron-donorske skupine. Pri tem je treba upoštevati, da uporaba atoma klora (Cl) pri načrtovanju feroelektričnih nematogenov še ni bila predhodno opisana. Pri homologih z razširjenim molekulskim jedrom je bila med ohlajanjem pod nematsko fazo opažena feroelektrična nematsko faza. Poleg tega smo pri nesubstituiranem homologu ugotovili, da je NF enantiotropna v širokem temperaturnem območju. Predstavljeni rezultati zagotavljajo dragocen vpogled v molekulsko načrtovanje feroelektričnih tekočekristalnih spojin.

DOI: 10.1039/D6MA00129G

Asst. Prof. Matjaž Gomilšek from the from the Condensed Matter Physics Department F5 at the Jožef Stefan Institute and the Faculty of Mathematics and Physics, University of Ljubljana has recently been elected to represent the magnetism community of Slovenia in the General Council (GC) of the European Magnetism Association (EMA) for a three-year term.
EMA is a non-profit organisation promoting the development of magnetism and magnetic materials in Europe by raising the visibility and impact of research on fundamental and applied magnetism.
The GC consists of representatives of the European countries active in magnetism research and defines the general policy of EMA, overseeing key activities such as the Joint European Magnetic Symposia (JEMS) conference and the European School on Magnetism (ESM).
Members of Slovenia’s magnetism community are warmly encouraged to reach out to Asst. Prof. Matjaž Gomilšek to share ideas, raise topics of interest, or explore opportunities to get involved in EMA activities (for additional information, see magnetism.eu).

Researchers from the Jožef Stefan Institute and the Faculty of Mathematics and Physics, University of Ljubljana, together with collaborators from Japan, the USA, and Greece, have reported the discovery of a robust metallic state in the molecular material Yb2CsC60. The study has been published in Nature Communications.

The work explores how strong electronic correlations behave in fullerene-based molecular solids containing a single “hole” in multiorbital electronic states. Using synchrotron X-ray diffraction, neutron scattering, Raman spectroscopy, NMR, X-ray absorption spectroscopy, and first-principles calculations, the team demonstrated that Yb2CsC60 remains metallic without undergoing a Mott transition.

The results reveal a remarkable analogy between correlated molecular p-electron systems and transition-metal d-electron materials, providing new insight into Hund-coupling physics and strongly correlated quantum matter. The newly synthesized orthorhombic fulleride may also open pathways toward discovering unconventional superconductivity in related molecular systems.

The paper:
“Survival of the metallic state in a single-hole multiband p-orbital molecular system”
K. Matsui, R. A. Klein, N. Yoshikane, J. Arvanitidis, M. Gomilšek, U. Klopčič, S. Kawaguchi, H. Yamaoka, N. Hiraoka, H. Ishii, Q. Zhang, S. Mori, H. Ishibashi, Y. Kubota, Craig M. Brown, Denis Arčon, and Kosmas Prassides. Nature Communications 2026.

Marta Lavrič, Luka Racman Knez and Andraž Rešetič, in collaboration with Valentina Domenici (Università degli studi di Pisa), have published an article entitled “Mechanical anisotropy in compressive-stress shape-programmed liquid crystal elastomers and polymer-dispersed liquid crystal elastomer composites” in the Nature Portfolio journal Soft Matter. This article provides insight into the mechanical properties of liquid crystal elastomers and polymer-dispersed liquid crystal elastomer (LCE) composites (PDLCEs) with a high-temperature persistent glass phase. It specifically focuses on compressive programming, which induces transverse mechanical anisotropy and a mesogen configuration with a negative order parameter. Directional stress–strain and thermomechanical tests reveal that, despite the elastic matrix, PDLCEs retain mechanical properties comparable to pure LCEs, highlighting the role of mechanical anisotropy together with inclusion alignment and geometry. The degree of mesogen ordering is evaluated in LCEs, while a modified Halpin–Tsai model captures the mechanical response of PDLCEs.

https://doi.org/10.1038/s44431-026-00022-z