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Dynamic reorganisation of calcite (1014) in humid ambients

Figure 1. (a) 4μπι x 4μιη AFM image of the calcite (1014) surface directly following cleavage in an ambient at 55% relative humidity (RH). The cleavage steps measure 0.3 lnm high, the height of one calcite unit cell, and exhibit a lightning-like shape with orientations in two distinct directions only. A small hillock is also evident to the centre of the image window, (b) After some 63 minutes have elapsed since the initial cleave, it is evident that a process of selective decoration by the nucleation of small islands has begun along orientation specific step edges . (c) Taken some 107 minutes after cleaving, this image shows that whilst the islands decorating steps have continued to grow, some nucleation of smaller islands has also occurred on the terraces themselves, (d) 10 pm x 10 pm area taken after 257 minutes, (e)-(f) Comparison of the terrace topography at reduced areas at 3 and 138 minutes after cleaving respectively. The total variation in the z-direction for (e) and (f) was 0.047nm and 0.142nm respectively.