AUTHOR=Mizokawa Takashi , Monney Claude TITLE=Excitonic insulator candidate Ta2NiSe5 and related transition-metal compounds studied by resonant inelastic x-ray scattering JOURNAL=Frontiers in Electronic Materials VOLUME=5 YEAR=2025 URL=https://www.frontiersin.org/journals/electronic-materials/articles/10.3389/femat.2025.1456147 DOI=10.3389/femat.2025.1456147 ISSN=2673-9895