Related Experiment Video
Updated: Jul 3, 2026
11:32
High Pressure Single Crystal Diffraction at PX^2
Published on: January 16, 2017
Pyramidal lead sulfide crystallites with high energy {113} facets
Dongbo Fan1, P John Thomas, Paul O'Brien
1School of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom.
Journal of the American Chemical Society
|July 30, 2008
Summary
Researchers developed a novel method to control crystallite shape, growing lead sulfide (PbS) pyramids at liquid interfaces. This technique allows for tunable dimensions and diverse crystal morphologies like rods and spheres.
Area of Science:
- Materials Science
- Crystallography
- Nanotechnology
Background:
- Controlling crystal morphology is crucial for tailoring material properties.
- Liquid-liquid interfaces offer unique environments for crystal growth.
- Previous methods for controlling crystallite shape have limitations.
Purpose of the Study:
- To report a new, generic method for controlling crystallite shape.
- To investigate the growth of lead sulfide (PbS) crystals in unusual pyramidal forms.
- To explore the influence of liquid-liquid interfaces on crystal habit and assembly.
Main Methods:
- Growing lead sulfide (PbS) crystals at the water-toluene interface.
- Utilizing phenomena unique to the liquid-liquid interface to direct crystal growth.
- Characterizing the resulting single-crystalline pyramids and their growth habits.
Main Results:
- PbS crystals were successfully grown in unique pyramidal shapes at the water-toluene interface.
- The pyramids exhibited single-crystalline structure with a specific growth habit (slow growth along the [113] direction).
- Pyramidal base dimensions were controllably varied between 575-1260 nm.
- Other morphologies, including rods and spheres, were obtained by altering interface properties.
Conclusions:
- A novel and generic method for controlling crystallite shape has been demonstrated.
- Liquid-liquid interfaces provide a powerful platform for directing crystal growth and assembly.
- This approach allows for tunable synthesis of various PbS nanostructures with potential applications in nanotechnology.
Related Concept Videos
02:42Ionic Crystal Structures
Ionic crystals consist of two or more different kinds of ions that usually have different sizes. The packing of these ions into a crystal structure is more complex than the packing of metal atoms that are the same size.
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
02:58Crystal Field Theory - Octahedral Complexes
Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
Tetrahedral Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
01:24The Seven Crystal Systems: Overview
Crystals with various point group symmetries belong to different crystal classes, which are synonymous terms. Despite being in the same class, crystals may have distinct shapes, like cubes and octahedra. There are 32 three-dimensional point groups, all of which are systematically divided into seven crystal systems.The basic cubic crystal system, exemplified by NaCl, features orthogonal vectors (α = β = �� = 90°) of equal lengths (a = b = c). When specific requirements are not imposed on the...
01:25Imperfections in Crystal Structure: Point, Line and Plane Defects
A perfect crystal, in theory, has a uniform structure with the same unit cell and lattice points throughout. However, any deviation from this periodic arrangement is known as an imperfection or defect. These defects can be categorized into three types: point, line, and plane defects.Point defects occur when there is a deviation from the ideal due to missing atoms, displaced atoms, or additional atoms. These imperfections might occur due to imperfect packing during crystallization or because of...
01:27Symmetry Elements in a Crystal
Crystal symmetry operations are isometric transformations that map objects onto indistinguishable copies while preserving distances, angles, and volumes. The simplest symmetry operation is translation, which shifts the entire infinite crystal lattice parallelly by a translation vector.Crystallographic rotations involve rotations by an angle of 2π/n around an axis without changing the positions of points on the axis. It is called the rotational axis of the symmetry, denoted by n. The combination...