Atomic And Molecular Spectroscopy By Rajkumar Pdf Extra Quality
Atomic And Molecular Spectroscopy By Rajkumar Pdf
IV. Molecular Physics: This branch of atomic and molecular physics investigates the details of the phenomena due to motion of the molecule. This branch covers the theory of rotational spectra, isotopic effects in chemical reactions, electronic transitions, optical spectra, and the interaction between the excited molecules and the environment.
Atomic and Molecular Physics is the most fundamental and oldest field in the domain of Quantum Physics. For more than more than a century, this field has been a testing ground for the quantum theory. More recently, the understanding of the structure of matter has been developing into a broad range of interdisciplinary subjects. Atomic and Molecular Physics, Radiation Chemistry and Quantum Chemistry are some of the most important areas.
The spectrum of the [emission]-[absorption] from an atom depends on its electronic structure and on the properties of the free electron gas. For an atomic electron it is related to the electronic spin. It is no real surprise that the electronic structure of atoms and molecules is very much dependent on the number of electrons in the atom/molecule. The simplest atom has one electron. For this electron there is no interesting anything to do. This electron is described by a wave function that is a product of 1s orbitals, but can only take on an integer value. The simple atom can do nothing else. That is, this atom is a single-electron atom. Its electronic structure can also be described by the atomic orbitals. For the 2-electron atom there are 2s orbitals, 2p orbitals, 2d orbitals, etc.
in the field of atomic physics, the term atomic physics has two different meanings. in its original sense, the term refers to the study of the structure and physical properties of the atom, while the term in the second meaning refers to the study of the structure of the atom when it is in an isolated system, such as in an individual molecule.
many of the spectroscopic techniques rely upon the distribution of electron orbitals throughout the atom. for example, the atom contains a positively charged nucleus which can hold electrons. the number of electrons depends on the atom’s atomic number. the number of electrons a given atom can hold depends on the atom’s electron affinity. the coulomb repulsion between the nucleus and its electrons also influences the number of electrons that an atom can hold. an atom’s chemical bond also influences its ability to hold electrons.
you can also think of each level of a certain type of atom as a band in the spectrum. however, the bands are not arranged in a particular order. each band is a vibrational level, and each vibrational level can be further subdivided into sub-levels. the bands in an atom’s spectrum correspond to the molecular vibrational levels that are involved in a particular electronic transition. for example, the first vibrational band for a hydrogen atom is a ground electronic state. the first vibrational band for a methane molecule is a ground electronic state.
molecules are the fundamental building blocks of the universe. they form the basis of all life and, as a result, they are the most important class of material in the world today. the study of molecules is called molecular spectroscopy. the study of atoms, which are the basic constituents of molecules, is called atomic spectroscopy. the world of molecules is studied by several branches of science called physics. these branches of physics are called molecular physics, atomic physics, and condensed matter physics. the study of the physical, chemical, and biological properties of solid matter is called condensed matter physics. the study of the properties of matter as it relates to the properties of the electrons is called atomic physics.