The spontaneous symmetry breaking in Ta2NiSe5 is structural in nature

Edoardo Baldini, Alfred Zong, Dongsung Choi, Changmin Lee, Marios H. Michael, Lukas Windgaetter, Igor I. Mazin, Simone Latini, Doron Azoury, Baiqing Lv, Anshul Kogar, Yao Wang, Yangfan Lu, Tomohiro Takayama, 7 Hidenori Takagi, 7 Andrew J. Millis, 9 Angel Rubio, 9, 10 Eugene Demler, and Nuh Gedik Department of Physics, Massachusetts Institute of Technology, 02139 Cambridge, Massachusetts, USA Department of Electrical Engineering & Computer Science, Massachusetts Institute of Technology, 02139 Cambridge, Massachusetts, USA Department of Physics, Harvard University, 02138 Cambridge, Massachusetts, USA Max Planck Institute for the Structure and Dynamics of Matter, Hamburg, Germany Department of Physics and Astronomy and Center for Quantum Materials, George Mason University, 22030 Fairfax, Virginia, USA Department of Physics, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany Department of Physics, Columbia University, New York, NY 10027, USA Center for Computational Quantum Physics, The Flatiron Institute, 162 Fifth Avenue, New York, NY 10010, USA Nano-Bio Spectroscopy Group, Departamento de F́ısica de Materiales, Universidad del Páıs Vasco, 20018 San Sebast́ıan, Spain (Dated: July 8, 2020)