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400 BCE
Democritus atomic model
The theory of Democritus held that everything is composed of "atoms" which are physically, but not geometrically indivisible; that between atoms, there lies empty space; that atoms are indestructible, and have always been and always will be in motion; that there is an infinite number of atoms and of kinds of atoms, which differ in shape and size. Of the mass of atoms, Democritus said, "The more any indivisible exceeds, the heavier it is." However, his exact position on atomic weight is disputed" -
Dalton Atomic Model
Dalton's atomic model was the first scientifically based atomic model, proposed in several steps between 1803 and 1808 by John Dalton, although the author called it more properly "atomic theory."
The model allowed to clarify why chemical substances reacted in fixed stoichiometric proportions, and why when two substances react to form two or more different compounds, then the proportions of these relations are whole numbers. -
Thomson's Atomic Model
Thomson's atomic model is a theory of atomic structure proposed in 1904 by Thomson, who discovered the electron in 1897, in the model, the atom is made up of negatively charged electrons in a positive atom, the assumption was called the “Raisin Pudding Model.” It postulated that electrons were uniformly distributed within the atom, suspended in a cloud of positive charge. The atom was thought of as a positively charged sphere with electrons spread out as small granules. -
Rutherford's Atomic Model
Rutherford's atomic model is an atomic model about the internal structure of the atom proposed in 1911.
Rutherford concluded that the mass of the atom was concentrated in a small region of positive charges that prevented the passage of alpha particles. Later he proposed a new atomic model that had a nucleus or center in which mass and positive charge are concentrated, and that in the extra nuclear zone are negatively charged electrons. -
Bohr's Atomic Model
Bohr's atomic model is a classical model of the atom, but it was the first atomic model in which a quantization based on certain postulates was introduced. Given that momentum quantization is adequately introduced, the model can be considered transactional in that it falls between classical and quantum mechanics. It was proposed in 1913 by Niels Bohr, to explain how electrons can have stable orbits around the nucleus and why atoms had characteristic emission spectra. -
Lewis' Model of the Cubic Atom.
The model of the cubic atom was one of the first atomic models in which the electrons of the atom were located at the eight vertices of a cube. This theory was developed in 1902 by Gilbert N. Lewis, who published it in 1916 in the article "The Atom and the Molecule"; served to realize the phenomenon of valence. It is based on Abegg's rule. It was later developed by Irving Langmuir in 1919. -
Sommerfeld's Atomic Model
The Sommerfeld atomic model is an atomic model made by the German physicist Arnold Sommerfeld. This model is a generalization of Bohr's atomic model from a relativistic point of view. In 1916, Sommerfeld perfected Bohr's atomic model trying to alleviate its two main defects. For that he introduced two basic modifications: almost elliptical orbits for electrons and relativistic velocities. In the Bohr model the electrons only rotated in circular orbits. -
Chadwick's Atomic Model
This atomic model is known as the quantum mechanical model of the atom. In 1932, James Chadwick bombarded beryllium atoms with alpha particles. An unknown radiation was produced. Chadwick interpreted this radiation as being composed of particles with a neutral electrical charge and the approximate mass of a proton. -
Heiseberg's Atomic Model
In February 1927, the young Werner Heisenberg developed a key piece of quantum theory, the uncertainty principle, with profound implications. The prevailing quantum theory in the early 1920s modeled the atom as having electrons in fixed quantized orbits around a nucleus. -
Schrödinger's Atomic Model
The atomic model of Schrödinger (1926) is a non-relativistic quantum model. In this model, electrons were originally viewed as a standing wave of matter whose amplitude rapidly decayed as it exceeded the atomic radius.Schrödinger's atomic model originally conceived of electrons as matter waves. Thus the equation would be integrated as the wave equation that described the evolution in time and space of said material wave. -
Diran-Jordan Atomic Model
He Atomic model of Dirac Jordan Is born with a base very similar to the Schrödinger model. However, the Dirac model introduces as a novelty the natural incorporation of the spin of the electron, as well as the revision and correction of certain relativistic theories.
The Dirac Jordan model was born from the studies of Paul Dirac and Pacual Jordan. Both in this case and that of Schrödinger, the basis has to do with quantum physics.