Now scientists have determined that a structure comprising 32 lead-sulfur pairs is the smallest possible cubic arrangement that exhibits the same coordination as bulk lead sulfide. (The coordination number is the number of nearest neighbors each atom in the crystal has.)
Researchers from McNeese State University in Louisiana, John Hopkins University in Maryland, and the University of Konstanz in Germany identified the "baby crystal" by running computer simulations that calculated the energy and geometry of different structures containing different numbers of atoms. They found that (PbS)32 is the smallest stable unit that possesses both the same cubic structure and coordination number as the bulk crystal. The researchers also experimentally tested their theoretical findings by gently depositing (PbS)32 clusters on a graphite surface where they could easily migrate and merge together to form larger nanoscale structures.
By using scanning tunneling microscope images to measure the dimensions of the resultant lead sulfide nano-blocks, the researchers confirmed that the (PbS)32 "baby crystals" had indeed stacked together as theoretically predicted.
The results, published in the AIP's Journal of Chemical Physics, show how small lead sulfide crystals come together to form larger units and could help provide a better understanding of the mechanisms involved in the formation of solids.
Article: "(PbS)32: A Baby Crystal" is published in the Journal of Chemical Physics.
Authors: B. Kiran (1), Anil K. Kandalam (2), Rameshu Rallabandi, (1) Pratik Koirala (2), Xiang Li (4), Xin Tang (4), Yi Wang (4), Howard Fairbrother (4), Gerd Gantefoer (3), and Kit Bowen (4).
Catherine Meyers | EurekAlert!
Turmoil in sluggish electrons’ existence
23.05.2017 | Max-Planck-Institut für Quantenoptik
Physicists discover that lithium oxide on tokamak walls can improve plasma performance
22.05.2017 | DOE/Princeton Plasma Physics Laboratory
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.
In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...
Dental plaque and the viscous brown slime in drainpipes are two familiar examples of bacterial biofilms. Removing such bacterial depositions from surfaces is...
23.05.2017 | Event News
22.05.2017 | Event News
17.05.2017 | Event News
23.05.2017 | Earth Sciences
23.05.2017 | Life Sciences
23.05.2017 | Physics and Astronomy