For some host•guest complexes the disassembly can be disabled at the ambient temperature by the complexation that subsequently heightens the barrier for disassembly. For example, a guest can enter the cavity of a host known as neocarcerand at room temperature and remain in the cavity at room temperature unless the portal is opened by heating because the docking of the guest at the cavity induces a host conformational change that consequently closes all cavity portals . The applications of carcerand and hemicarcerand are however limited because their complexes cannot be formed in situ and adiabatically. Although neocarcerand can form its complexes in situ and adiabatically , the applications of the neocarcerand complexes are also limited by their slow complexation rates. This underscores the need to understand how two molecules self-assemble into a noncovalent irreversible complex and what accelerates their assembly as these high-level questions hold the key to designing noncovalent irreversible bimolecular complexes with fast complexation rates for broad applications.