The 1 st flash increased TNP to ~2350 K for three seconds, resulting in sublimation of only ~37 kDa (less than the width of the mass points), therefore a second flash to TNP ≈ 2700 K was applied, causing sublimation of ~216 kDa over two seconds. When O2 was added to probe reactivity, there was no significant mass loss, i.e., the NP remained inert. After switching off the O2 flow, the NP was flashed to ~2900 K for 12 seconds, causing a much larger mass loss of ~7.7 MDa accompanied by a 6e decrease in the NP charge. As noted in the discussion of Figs. and, NPs often undergo thermionic electron emission, especially when first heated to higher temperatures, however, this increases Q in increments of +e, giving rise to well defined steps in secular frequency (Fig. ). The simultaneous decrease in M and Q observed during flash heating of the diamond NP, is attributed to loss of positively charged fragments from the NP. In this case, where the NP was clearly a large aggregate of primary nanodiamonds, fragmentation may have involved loss of individual nanodiamonds or small aggregates. Given that the estimated TNP during the flash was high, rapid sublimation also must have occurred, and it is not possible to separate the mass losses due to fragmentation and sublimation.