chemical beam epitaxy

关于结构化学束外延

Structural chemistry refers to the study of the structure and properties of chemical compounds and the relationships between them. It also includes the investigation of how those structures and properties interact to form substances and how they react when exposed to different stimuli. Structural chemistry is an important field of study because it helps scientists to better understand the nature and behavior of matter, including the properties of both simple and complex molecules.

In structural chemistry, the physical, electronic, and spectral properties of a compound are studied. Physical properties such as melting point, boiling point, mass, and volume are used to characterize a material. The electronic properties, such as the materials band gap and dielectric constant, are important in determining the type of semiconductor material used in applications. Spectral properties such as infrared and Raman spectroscopies are used to identify the structure and vibrational frequency of a material.

In addition to studying the structure and properties of compounds, structural chemistry also looks at the interactions between compounds in solution. These interactions can be determined using a variety of techniques, such as nuclear magnetic resonance (NMR), infrared spectroscopy, ultraviolet-visible spectroscopy, and X-ray diffraction. These techniques allow chemists to determine not only the structure of a molecule, but also the way it interacts with its environment.

Structural chemistry is also important in understanding the structure of polymers. Polymers are composed of many repeating units of atoms or molecules bonded together. How these repeating units are arranged can influence the physical and mechanical behavior of a polymer. For example, some polymers may be more flexible than others and others may be more durable.

In addition to studying the properties of molecules, structural chemistry also looks at the architecture of molecular systems. This includes the structure of the bonds formed between atoms and molecules, and how those bonds change in response to environmental stimuli such as temperature, light, or pressure. This kind of research helps to uncover the details of the structures and functions of biomolecules.

finally, structural chemistry also explores the concept of supramolecular chemistry, or the study of the interactions between molecules beyond the level of individual atoms and molecules. Supramolecular chemistry focuses on the assembly of molecules into larger assemblies, such as crystals and other materials. This approach can be applied to both synthesis and design of materials, enabling chemists to create new materials with desirable properties. It can also help to understand the physical structure of proteins and other biologically important molecules, unlocking the secrets of life.

Chemical-vapor deposition (CVD) method is one of the most important methods of nanomaterial synthesis. This method is based on the principle of gas-solid reaction and makes use of the reaction between certain chemical gases (reactants) and a substrate at elevated temperatures. The molecules of the chemical gases react when they come in contact with the substrate and form target materials on its surface. Therefore, this method is widely used to produce silicon oxide (SiO2) or carbon nanomaterials (CNTs) as well as some other metal/alloy nanoparticles.

The principle of CVD is quite simple. The two main components for CVD are the gas-solid reaction and the temperature ramp rate. Precursor chemical gas reactants are passing an evenly chemical reaction potential into the chamber. The temperature ramp rate is used to control the rate of reaction, and the chemical reactions of the reactants are greatly affected by the surface of the substrate. When chemical vapor deposition is employed, certain gases are chemically reacted with the substrate, resulting in the formation of thin layered materials. Therefore, the metal/alloy nanoparticles, silicon oxide and carbon nanomaterials can be deposited onto the surface of the substrate using CVD.

The resulting chemical-vapor-deposited material exhibits a wide range of properties, depending on the nature of the chemical gases and the degree of deposition. Not limited to nanoparticles, CVD method can also be used to synthesize nanowires, nanotubes, nanocoatings, and other types of nanostructures. CVD method offers a low cost and high-yield production of nanomaterials and is widely used in the fields of medical science, microelectronics, and materials science. Furthermore, the versatility of this method enables the development of novel materials and structures not achievable with conventional techniques.