On another thread on this website it mentioned how it was possible to melt diamonds, but what would be the micro-level occur for that to happen. This question applies to Silicon Oxide aswell. They both have infinite structures. Which bonds would break or even weaken for them to transition states? For example, when a regular covalent solid is heated, the intermolecular forces of attraction weaken and the solid melts. How would that work for a structure like that of diamond?

  • $\begingroup$ See, all bonds in diamond are exactly the same. Just how can we tell which of them would break? (Some would, that's for sure.) What does "which" even mean in this context? $\endgroup$ – Ivan Neretin Oct 4 '19 at 7:21
  • $\begingroup$ you might consult a phase diagram : phycomp.technion.ac.il/~anastasy/teza/teza/node5.html $\endgroup$ – Buck Thorn Oct 4 '19 at 9:07
  • $\begingroup$ see also: chemistry.stackexchange.com/questions/6068/… $\endgroup$ – Buck Thorn Oct 4 '19 at 9:22
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    $\begingroup$ Why do you say "when a regular covalent solid is heated, the intermolecular forces". To zeroth order that's not true, an appreciable proportion of the atoms just start having enough thermal energy to overcome them. And given it is not all atoms that have sufficient think how that might answer your question. $\endgroup$ – Ian Bush Oct 4 '19 at 9:27
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    $\begingroup$ The comments in this question come pretty close to providing the answer. If necessary, I can organise the concepts a bit more in a new answer here. $\endgroup$ – Nicolau Saker Neto Oct 4 '19 at 13:14