Polarized optical microscope. Single crystals grown under the dropcasting procedure were placed on a Nikon H550S with a high-speed camera (Infinity 1) and heating stage (Linkam 402). The chamber was sealed with a magnetic lid and O-ring during heating. The temperature ramp was kept at a constant 5 °C min -1 . Videos were recorded at framerates ranging from 1 to 7.5 fps. Video analysis was performed using a python program to obtain an average intensity value of a given crystal at each frame.