Amit K. Mondal,1 Noam Brown,2,3 Suryakant Mishra,1 Pandeeswar Makam,2 Dahvyd Wing,6 Sharon Gilead,2 Yarden Wiesenfeld,4 Gregory Leitus,5 Linda J. W. Shimon,5 Raanan Carmieli,5 David Ehre,6 Grzegorz Kamieniarz,6,7 Jonas Fransson,8 Oded Hod,3 Leeor Kronik,6 Ehud Gazit,2 and Ron Naaman1
1) Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot 76100, Israel.
2) School of Molecular Cell Biology and Biotechnology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801, Israel.
3) Department of Physical Chemistry, School of Chemistry, The Raymond and Beverly Sackler Faculty of Exact Sciences and The Sackler Center for Computational Molecular and Materials Science, Tel Aviv University, Tel Aviv, IL 6997801.
4) Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA.
5) Department of Chemical Research Support, Weizmann Institute of Science, Rehovot 76100, Israel.
6) Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot 76100, Israel.
7) Faculty of Physics, A. Mickiewicz University, 61-614 Poznań, Poland.
8) Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden.
Room-temperature, long-range (300 nm), chirality-induced
spin-selective electron conduction is found in chiral metal–organic
Cu(II) phenylalanine crystals, using magnetic conductive-probe atomic
force microscopy. These crystals are found to be also weakly
ferromagnetic and ferroelectric. Notably, the observed ferromagnetism
is thermally activated, so that the crystals are antiferromagnetic at
low temperatures and become ferromagnetic above ~50 K. Electron
paramagnetic resonance measurements and density functional theory
calculations suggest that these unusual magnetic properties result
from indirect exchange interaction of the Cu(II) ions through the
chiral lattice.
