The existence of polymorphs analogous to wurtzite among these elements is not surprising, because the two types of structure are so similar geometrically that the energy differences between them must be small. A wurtzite-like polymorph of silicon has already been synthesized. For carbon a ...
Lonsdaleite, often called hexagonal diamond, is an allotrope of carbon with a unique structure that theoretically makes it harder than diamond. Unlike diamond's cubic crystal structure, Lonsdaleite has a hexagonal arrangement, which could make its bonds stronger under certain conditions. Diamonds are f...
Our experiment provides new insights into the processes of the shock-induced transition from graphite to diamond and uniquely resolves the dynamics that explain the main natural occurrence of the lonsdaleite crystal structure being close to meteor impact sites. Shock synthesis of diamond and even ...
structure (solids and liquids)gold, Augallium, Gastrontium, SrThe title compound is prepared by induction melting of the elements (Ta tube, Ar flow, 1300 K, 10 min) followed by annealing at 770 K (1 d).doi:10.1002/chin.201435003
The term "lonsdaleite," used to denote carbon materials found in meteorite impact craters and diamond crystals with 2H polytype structure, is rather ambiguous, since no pure hexagonal diamond has been identified in carbon phases found at meteorite fall sites. 展开 ...
Magnesium and Cadmium in Covalently-Bonded Lonsdaleite Networks: Synthesis, Structure, and Bonding of AETMg2 and SrTCd2 (AE = Ca, Sr; T = Pd, Ag, Pt, Au) The alkaline earth metal compounds AETMg2 and AETCd2 (AE = Ca, Sr; T = Pd, Ag, Pt, Au) were synthesized by induction-meltin...
We formulate a unit-cell model of open-cell elastic foams. In this model, a foam consists of four-bar tetrahedra arranged in the hexagonal diamond structure known as Lonsdaleite. The parameters of the model are the Young's modulus of the bars and a few geometric parameters, the values of ...
Structure and Optical Properties of Nanocrystals and Quantum Dots with Diamond, Lonsdaleite, Sphalerite and Wurtzite StructuresNanostructureNanoshellNanoorbitQuantum DotPoint GroupSymmetry TheoryThe formulas for calculation of the number of atoms and their space distribution in nanocrystals and quantum dots ...
The structural and spectroscopic characteristics of isolated lonsdaleite particles that have a relatively large size and monocrystalline structure are given for the first time. The results of these studies can be used not only for simulating the processes of natural diamond formation, but also for ...
As a result, the molecular dynamics simulations clarified the effect of the hexagonal structure on both the fracture toughness and the fracture mechanism, as well as the excellent thermal stability of lonsdaleite.Hiroaki TanakaShoichi ShimadaInternational Conference of the European Society for Precision ...