Isomerism is the phenomenon whereby certain compounds, with the same molecular formula, exist in different forms owing to their different organisations of atoms. The concept of isomerism illustrates the fundamental importance of molecular structure and shape in organic chemistry.
By signing the nuclear deal, Iran has given up that nuclear umbrella for as long as two decades and made the case for the United States to further strengthen the conventional military capacities of Israel and the GCC.
Iran, the United States and five other world powers have sealed a breakthrough framework agreement outlining limits on Iran's nuclear programme, despite attempts by Israel and Saudi Arabia to thwart the deal. Al Jazeera spoke with four analysts about why Saudi Arabia and other Gulf countries, along with Israel, are upset about the agreement.