High energy ahead! The appearance of new high energy density explosive molecules

There is an upper limit of packing density for the traditional organic explosives composed of carbon, hydrogen, nitrogen and oxygen, so that there are few single explosives with a crystal density of more than 2G / cm3 at room temperature Among them, the representative high-density explosive is hexanitrohexaazaisowurtzitane, but the lack of cost, preparation process and safety of the explosive has been restricting its large-scale application Therefore, the synthesis of a new type of high-energy density materials (HEDMS) with better comprehensive properties by molecular design is one of the scientific challenges faced by scientists in the field of energetic materials at home and abroad Synthesis route of icm-101 (source: nature Communications) to achieve the above breakthrough, Institute of chemical materials, Chinese Academy of Engineering Physics The team of scientists creatively adopted the material genome method to independently design, with the highly symmetrical 1,3,4 - (oxadiazole) structure as the parent, directionally introduced nitramine group to improve energy, and adopted strategies such as molecular hydrogen bond and π - π stacking to improve density Through these two steps of reaction, high-efficiency synthesis was carried out, and a new high-energy density explosion with the measured density of 2G / cm3 was prepared The drug molecule was named as icm-101 "The new explosive has the same energy level as the classical high-energy explosive CL-20, no transgranular phenomenon, simple preparation method, low production cost, and has certain practical application potential." Zhang Qinghua, the leader of the energetic molecular creation team and expert of the national "thousand talents plan", said that the research results were highly praised by the reviewers of nature communications, and said that it was "an important progress in exploring alternatives to synthetic high-energy explosive CL-20" According to the internationally accepted view, the explosive can be divided into four generations according to the propagation speed of detonation wave The structural formula of TNT, RDX, HMX, CL-20, n-no2 bond seems to be the standard (source: Network) The first generation of explosives is "nitroglycerin", which brings wealth and reputation to Nobel The chemical properties of pure nitroglycerin are very unstable and the sensitivity is too high The stability of digested glycerin absorbed by seaweed soil was improved immediately, and its application was promoted rapidly, which changed the history of World War TNT (TNT), the second generation explosive, played an important role in World War II TNT is a kind of high explosive which is synthesized by artificial organic synthesis Its explosive ability is strong enough and its property is stable It can be used in the dense fire shooting of mechanism gun, which greatly improves the cruelty of war, and it is still widely used until now The third generation explosive, RDX (cyclotrimethylene trinitrate), was produced after World War II The detonation speed reached 8500-8600 M / s, which can be used to suppress and strike multiple rocket heavy guns on a large scale, and can improve the power and range of weapons on a large scale Secondly, Octogen (HMX), with detonation velocity of 9000 m / s, impact sensitivity slightly higher than TNT, easy initiation, good stability and high comprehensive performance, was used in the non-contact asymmetric operations of long-range rocket missiles in the Gulf War The fourth generation of explosive CL-20, known as hexanitrohexaazaisowurtzitane, is a non nuclear single explosive with the highest energy and the most powerful force known for its practical application Its detonation speed is up to 9500 M / s, known as the fourth generation of explosive, also known as "breakthrough energetic material" It is an epoch-making new high explosive for military use, which is well known in the world of explosive pharmacy The birth of this type of explosive has also brought new development opportunities for the efficiency improvement and miniaturization of a number of weapons including missiles and nuclear devices Compared with HMX, the energy density of CL-20 is 8% - 10% higher and its burning rate is twice as fast Paper link: www.nature.com/articles/s41467-017-00286-0