Can a cusp catastrophe model describe the effect of sanctions on exchange rates?

Fluctuations of exchange rates, like any other economic variables, are very common in financial markets. However, sometimes because of political and economic tensions, exchange rates exhibit abrupt crashes that lead to structural break. In this paper, the author answers the question whether a catastrophe model can be used for modeling the collapse of exchange rates caused by economic sanctions. For this goal, he uses a cusp catastrophe model for fitting the dynamics of fluctuations of the Iranian Rial against the US Dollar. Using two sentiment variables, i.e. trading volume and ratio of institutional to individual trades of gold futures contracts, the author has shown that the collapse of Iranian currency can be best explained by cusp catastrophe theory.