At lower temperatures (≈255 K [1] ), however, the original high-symmetry para electric-orthorhombic state is restored. Symmetry associated with this re-entrant phase transition has unusually, therefore, increased on cooling. Some observations show that this generates a local dip in the heat capacity, [1,2] stalling entropy reduction on decreasing temperature. [1] Strange symmetry transformations also occur in flux-grown barium titanate crystals, where highly ordered "Forsbergh Patterns" can first appear and then subsequently disappear, as temperature is monotonically varied. [3,4] Most recently, heating has been seen to cause high symmetry labyrinthine ferroelectric domain patterns to give way to lower symmetry stripe arrays: an effect classified as an "inverse transition". [5] Clearly, symmetry changes can therefore occasionally occur in the opposite sense to that normally seen. While fundamental thermodynamic laws are not broken, such cases are unusual, arresting, and worthy of note. [6]

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The behaviour of palladium & nickel deposited on mechanically exfoliated samples of 2D transition metal dichalcogenides (MoS 2 , WS 2 , and WSe 2 ) via e-beam evaporation was investigated.Sputtering of metals on the flakes allowed for interaction of the metal and TMD to be investigated on the Å scale in an aberration-corrected transmission electron microscope. By low energy sputtering metals can be deposited on 2D materials without causing damage to the thin flakes. The materials interaction is investigated on the atomic scale via high resolution scanning transmission electron microscopy in high angle annular dark field imaging. Initially, the effect of thermal annealing on the stability of the Pd-2D interaction was investigated, revealing the remarkable difference in particle stability between the 2D materials. Nickel deposition however only resulted in oxidised amorphous particles. The oxide particles' cross-sectional area and circularity were independent of the TMD substrate thickness or type, and deposition rate.

Conducting domain walls (DWs) in ferroelectrics is an emerging research focus in nano-electronics [1,2]. Previously overlooked, these walls have recently been reported to possess diverse functional characteristics that are completely different from the domains that they delineate [3][4][5]. They can have their own distinct chemistry and magnetic behavior [6], and in turn represent a completely new sheet phase. The characteristics of these confined regions are believed to have the same exotic functional behaviours as seen in 2D materials such as graphene, opening up a plethora of possible electronic applications. In addition, the walls have the unique property of being 'agile'; they can be created or destroyed and even be controllably moved by an external field. However, this is an area of research at its very early stages, with a great deal of the fundamental physics still unknown. Since the region of interest (the domain wall) is atomically thin and dynamic, it is essential for the physical characterization to be at this scale and be time-resolved.

In the previous decade, open-course python packages, such as Hyperspy [1], have gifted researchers in the field of electron microscopy (EM) with easy to use, well-documented, and most-importantly flexible analysis tools. Although there is a small initial barrier for those not versed in programming and scripting, the simplicity and depth of documentation of these python packages allow many to contribute to their development. The power of these programs is the ability to adapt and create code for many areas of data and image analysis. Combining python-based packages developed for EM and material science such as Hyperspy [2], RigidRegistration [3], Atomap [4], PyPrismatic [5,6] and Atomic Simulation Environment (ASE) [7] allows for automated and reproducible image analysis.136