Quantum and Materials Chemistry

- Materials Chemistry

Materials chemistry involves the use of chemistry to design and synthesize materials with interesting or potentially useful physical properties such as magnetic, optical, structural or catalytic properties. It also involves an understanding of the characterization, processing and molecular level of these substances.

- Matter 

In classical physics and general chemistry, matter is any matter that has mass and occupies space through volume. All objects that can be touched in everyday life are ultimately made up of atoms, which are made up of interacting subatomic particles, and in everyday and scientific use, "matter" generally includes atoms and anything made of them, and any particle (or combination of particles) as if they had rest mass and volume. 

However, it does not include massless particles, such as photons, or other energetic phenomena or waves, such as light or heat. Matter exists in various states (also called phases). These include classical everyday phases such as solids, liquids and gases - for example water in the form of ice, liquid water and gaseous vapour - but other states are also possible, including plasma, Bose-Einstein condensation, Fei Mion condensation and quark-gluon plasma. 

- Quantum

Quantum is essentially a reference to quantum mechanics, which focuses on atomic and subatomic particles, their energies, their motions, and their interactions. 

Larger accumulations of atoms and molecules behave more in a statistical or aggregated manner, where quantum mechanical properties (quantum effects) are averaged out. Quantum Information Science and its subfields focus on the level of quantum mechanics, where special features of quantum mechanics (quantum effects) are visible and can be exploited and manipulated.

- Quantum Chemistry

Quantum chemistry is the application of quantum mechanics in chemistry, particularly to the behavior of electrons, including excited atoms, molecules, and chemical reactions. 

The application of classical computing to quantum chemistry is called computational chemistry.

- Quantum Materials

A quantum material is one whose electronic or magnetic properties are best described as having nontrivial quantum-mechanical origins -- in other words, those materials whose electronic or magnetic properties cannot be adequately described by classical particles or calculations that do not take into account the full characteristics of the system. properties. Determining whether the properties of materials have quantum origins is a highly active field.

Quantum materials are vaguely defined as materials that don’t behave according to laws of classical physics. Examples include superconductors, complex magnets or topological materials. These materials can lead to many novel technologies, including faster computers, fault tolerant quantum computers, improved optical sensors or levitating trains. 

- Quantum Chemistry in Materials Science

Applying electronic structure theory in materials science is a challenging task, as accurate descriptions of molecular structures or system-relevant details are often unknown or poorly characterized. Therefore, the task of theory is usually to evaluate whether a hypothesis is plausible or what factors might affect a given property or phenomenon. While this rarely requires quantitative results obtained by advanced ab initio methods, it often requires consideration of structural diversity or the inclusion of effects such as solvent and environmental influences. 

While theory can be used as a powerful tool to rationalize connections between atomic and electronic structure and properties or mechanisms, the design of relevant models requires close collaboration with experimentalists. Only by jointly solving related problems can the full potential of meaningful "computational experiments" be realized.

- Computational Chemistry

Computational chemistry is a branch of chemistry that uses computer simulations to help solve chemical problems. It uses theoretical chemical methods incorporated into computer programs to calculate the structure and properties of molecules, groups of molecules, and solids. 

This is essential because, with the exception of relatively recent results on molecular hydrogen ions (dihydrogen cations), the quantum many-body problem cannot be solved analytically, let alone in closed form. While computational results often complement information obtained from chemical experiments, it can in some cases predict hitherto unobserved chemical phenomena. It is widely used in the design of new drugs and new materials. 

Examples of such properties are structure (i.e. the expected positions of the constituent atoms), absolute and relative (interaction) energies, electron charge density distribution, dipole and higher multipole moments, vibrational frequencies, reactivity or other spectral quantities , and the cross section for collisions with other particles.

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