Cryo 4D-STEM Data Set: isotactic Polypropylene/ Ethylene-Octene Copolymer Interface

<p><strong>Sample:</strong> Data is taken of a iPP/EO (DOW ENGAGE^TM 8540) blend interface. The blend was cryo-microtomed to a nominal slice thickness of 50nm. Transmission electron microscopy was performed using the TEAM I microscope at the Lawrence Berkeley National Laboratory using a Gatan K3 detector and Continuum spectrometer.</p> <p><strong>Data Set 12: </strong>This work was performed at -185&deg;C under liquid nitrogen cooling with a 300kV accelerating voltage and a semi-convergence angle of 0.5mrad which yielded a diffraction-limited probe with a full-width half-max of 2nm. The beam was rastered with a step size of 5nm&nbsp;over a 505 &times; 500nm² field of view. The electron dose per sample area over the entire scan is 20 e^-/&Aring;². However, 4D-STEM is a converged probe technique in which ~80% of the beam fluence is contained within 1.74 &times; the FWHM of the probe. Using 1.74 &times; the FWHM of the probe as the diameter to calculate the irradiated sample area yields a dose of 60 e^-/&Aring;² for this data set. &nbsp;Gold nanoparticles were used to calibrate the reciprocal space pixel size as well as measure the elliptical distortion present in the data set.</p> <p><strong>Data Set 18: </strong>This data was taken at -185&deg;C under liquid nitrogen cooling with a 300kV accelerating voltage and a semi-convergence angle of 0.14mrad which yielded a diffraction-limited probe with a full-width half-max of 10nm. The beam was rastered with a step size of 10nm over a 1.4 &times; 1.4&mu;m² field of view. The electron dose per sample area over the entire scan was 0.50 e-/&Aring;² while the dose per probe area was 0.64 e-/&Aring;². Gold nanoparticles were used to calibrate the reciprocal space pixel size.</p> <p><strong>Data Set 19: </strong>This data was taken over the exact same area as Data Set 18 to give a comparison under larger dose accumulation. The data was obtained with the exact same parameters and under the same experimental conditions as Data Set 18.</p>