CMSP Seminar (Atomistic Simulation Webinar Series): Wednesday 10 February 2021 at 11 a.m.

[Ivanissevich Nicoletta]

Virtual - Zoom Meeting

CMSP Atomistic Simulation Webinar Series
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* * * *Wednesday, 10 February 2021 at 11:00 a.m.** * *

Speaker: *Maytal Caspary Toroker *(Department of Materials Science and 
Engineering, Technion - Israel)

Title: *Modeling polaron hopping in ternary spinel oxides*

Register in advance at:
https://zoom.us/meeting/register/tJEufuqhrzMpE928Jn8ylj2EnACS0uPmTyB1
After registering, you will receive a confirmation email containing 
information about joining the seminar.


Abstract:

The small-polaron hopping model has been used for several decades for 
modeling electronic charge transport in oxides. Despite its 
significance, the model was developed for binary oxides, and its 
accuracy has not been rigorously tested for higher-order oxides. To 
investigate this issue, we chose the Mn_x Fe_3-x O_4 spinel system, 
which has exciting electrochemical and catalytic properties, and mixed 
cation oxidation states that enable us to examine the mechanisms of 
small-polaron transport. Using a combination of experimental results and 
DFT+/U/ calculations, we find that the charge transport occurs only 
between like-cations (Fe/Fe or Mn/Mn). And due to asymmetric hopping 
barriers and formation energies, we find that the (Mn)2+(Oh) polaron is 
energetically preferred to the (Fe)2+(Oh) polaron, resulting in an 
asymmetric contribution of the Mn/Mn pathways.


CMSP, Condensed Matter & Statistical Physics Section
http://www.ictp.it/research/cmsp.aspx

The Abdus Salam International Centre for Theoretical Physics
https://www.ictp.it/  <https://www.ictp.it/>

    
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