The Mott insulator YVO3 with TN = 118 K is revisited to explore the role of spin, lattice and
orbital correlations across the multiple structural and magnetic transitions observed as a function
of temperature. Upon cooling, the crystal structure changes from orthorhombic to monoclinic at
200 K, and back to orthorhombic at 77 K, followed by magnetic transitions. From the paramagnetic
high temperature phase, C-type ordering is first observed at 118 K, followed by a G-type spin re-
orientation transition at 77 K. The dynamics of the transitions were investigated via inelastic neutron
scattering and first principles calculations. An overall good agreement between the neutron data
and calculated spectra was observed. From the magnon density of states, the magnetic exchange
constants were deduced to be Jab = Jc = -5.8 meV in the G-type spin phase, and Jab = -3.8 meV,
Jc = 7.6 meV at 80 K and Jab = -3.0 meV, Jc = 6.0 meV at 100 K in the C-type spin phase.
Paramagnetic scattering was observed in the spin ordered phases, well below the C-type transition
temperature, that continuously increased above the transition. Fluctuations in the temperature
dependence of the phonon density of states were observed between 50 and 80 K as well, coinciding
with the G-type to C-type transition. These fluctuations are attributed to optical oxygen modes
above 40 meV, from first principles calculations. In contrast, little change in the phonon spectra is
observed across TN.This work has been supported by the Department of
Energy, Grant number DE-FG02-01ER4592. This work
was also partly supported by the Materials Research Sci-
ence and Engineering Centers, National Science Founda-
tion, Grant number DMR-1720595, by providing sample
used in this work and by the National Institute of Stan-
dards and Technology, US Department of Commerce, in
providing computing resources for DFT calculations used
in this work.Center for Dynamics and Control of Material
