BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Events//NONSGML v1.0//EN
METHOD:PUBLISH
BEGIN:VEVENT
DTSTART;TZID="Pacific Time (US & Canada)":20210201T161000
DTEND;TZID="Pacific Time (US & Canada)":20210201T170000
SUMMARY:Department of Chemistry Seminar – Dr. Anatoly Frenkel
LOCATION:Online
DESCRIPTION:Anatoly Frenkel, Department of Materials Science and Chemical Engineering, Stony Brook University\n\nJoint appointment: Division of Chemistry, Brookhaven National Laboratory\n\nHost: Liane Moreau\n\nTitle: Decoding Reactive Structures in Nanocatalysts Hidden in their X-ray Absorption Spectra\n\nAbstract: Detecting the active sites of nanocatalysts and obtaining their structural descriptors in reaction conditions is a major challenge. The main reason is the paucity of experimental techniques that can provide atomic-level information for metal species in harsh reaction conditions, such as high temperature and pressure, low metal loadings, and a realistic reactor environment. Here I will report on the use of X-ray absorption spectroscopy (XAS), enabled by machine learning, for determining the three-dimensional geometry of monometallic and alloy nanoparticles. Artificial neural network (NN), an example of a supervised machine learning approach, is used to unravel the hidden relationship between the XANES features and descriptors of material geometry and electronic properties. In other words, we trained a computer to learn how to ‘invert” the unknown spectrum and map it onto the underlying structural and electronic descriptors. Using an unsupervised machine learning approach, we bracketed the a priori unknown number of descriptors by the number of nodes in the latent space of the autoencoder. In both cases, neural network training was performed by using theoretical spectroscopy codes. These applications are demonstrated by reconstructing the geometric shapes and compositional distributions in nanocatalysts (nanoparticles and size-selective clusters) studied under in situ and operando conditions from their XAS spectra. I will discuss opportunities for applying these methods to other spectroscopies and other functional nanoscale systems.\n\n************************************************************************************\n\nZOOM INFORMATION:\n\nImportant Note: Both internal and external WSU meeting attendees must be signed into Zoom to join the meeting.\n\nPlease refer to this guide on Joining WSU Zoom Meetings before trying to join the meeting:\n\nhttps://confluence.esg.wsu.edu/display/KB/Zoom+-+Joining+Meetings+and+Best+Practices\n\nJoin from PC, Mac, Linux, iOS, or Android: https://wsu.zoom.us/j/96933693820?pwd=emVoNDlWOUl5VnhGUVV5ZDdFOVE0Zz09\n\nMeeting ID: 969 3369 3820\n\nPasscode: 073974\n\nJoin from WSU Conference Room System (Polycom)\n\n1. Using the touch panel, or remote control,  select 'Place a Call'\n\n2. Enter the IP Address including periods: 162.255.37.11\n\n3. Press the pound key twice '##'\n\n4. Enter the Meeting ID: 969 3369 3820\n\n5. Press 'Call'\n\n6. Enter Passcode: 073974\n\nJoin from Conference Room System with SIP\n\n96933693820@zoomcrc.com\n\nShare Screen/Content Wirelessly\n\nGo to https://share.zoom.us and enter Meeting ID: 969 3369 3820\n\nPhone Call (long distance)\n\n+1 253 215 8782\n\n+12532158782,,96933693820# US (One Tap Mobile Call)\n\nFind your international phone number: https://wsu.zoom.us/u/adiXMUkN2f\n\nFor technical support with WSU conference rooms, contact your local IT team\n\nFor support or feature requests, please go to https://its.wsu.edu/wsu-video-conferencing-services/\n\n
BEGIN:VALARM
ACTION:DISPLAY
DESCRIPTION:REMINDER
TRIGGER;RELATED=START:-PT00H15M00S
END:VALARM
END:VEVENT
END:VCALENDAR