Transmission electron microscopy of a model crystalline organic, theophylline

Electron Microscopy and Analysis Group Conference 2015

Cattle, J.^1 ; S'Ari, M.^1 ; Hondow, N.^1 ; Abellán, P.^2 ; Brown, A.P.^1 ; Brydson, R.M.D.^1

Institute for Materials Research, School of Chemical and Process Engineering, University of Leeds, Leeds

LS2 9JT, United Kingdom^1

SuperSTEM, STFC Daresbury Laboratories, Keckwick Lane, Warrington

WA4 4AD, United Kingdom^2

关键词: Accelerating voltages;    Atomic lattice;    Beam damage;    Bright fields;    Critical electron dose;    Graphene films;    Sample temperature;    TEM grids;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/644/1/012030/pdf
DOI  :  10.1088/1742-6596/644/1/012030

来源: IOP

【 摘 要 】

We report on the use of transmission electron microscopy (TEM) to analyse the diffraction patterns of the model crystalline organic theophylline to investigate beam damage in relation to changing accelerating voltage, sample temperature and TEM grid support films. We find that samples deposited on graphene film grids have the longest lifetimes when also held at -190 °C and imaged at 200 kV accelerating voltage. Finally, atomic lattice images are obtained in bright field STEM by working close to the estimated critical electron dose for theophylline.