Category archives: DIPC Computational and Theoretical Chemistry

As early as the 1970s, it was suggested that one-particle reduced density matrix functional theory could be an attractive alternative formalism to wave function-based methods. Unfortunately, calculations based on exact functionals generated by the constrained-search formulation are computationally too expensive, which has prompted the development of approximate functionals for practical applications. The functionals currently in […]

Light emission (fluorescence or phosphorescence) in organic molecules, in the vast majority of cases, proceeds from the lowest energy excited state irrespective of the excitation energy used. This is known as the Kasha’s rule, which states that most of the molecules are emissive from the lowest energy, same (ground state) spin multiplicity, S1 excited state […]

Nonlinear optics is concerned with the optical properties of matter subjected to intense electromagnetic fields. For nonlinearity to manifest itself, the external field should not be negligible compared to the internal fields of atoms and molecules of which the matter consists. Lasers are capable of generating external fields sufficiently intense for nonlinearity to occur. Actually […]

Nanothreads are one-dimensional covalently bonded materials, with all “backbone” bonds saturated in the organic sense, the first of which was made from polymerization of benzene in the solid state. Nanothreads are thicker than conventional hydrocarbon polymers such as polyethylene and thinner than traditional nanowires: as ladder polymers, they are examples of the thinnest possible rigid […]

A kinetic isotope effect (KIE) has been observed for the generation of hydrogen from the hydrolysis of a hydrosilane catalysed by a silyl-iridium(III) complex. This and other experimental evidence together with theoretical calculations have been used to demonstrate the participation of hydrogen quantum tunnelling in this catalytic process. KIE is a phenomenon associated with isotopically […]

Nanothreads are one-dimensional nanomaterials composed of a primarily sp 3 hydrocarbon backbone, typically formed through the compression of small molecules to high pressures. In 2015, it was found that the slow room-temperature compression of benzene produced crystalline, one-dimensional polymers composed of diamond-like bonds. These diamondoid materials that border nanotubes and polymers are predicted to possess […]

If we are asked what a metal is, most likely we would think almost automatically in those elements that we see as lustrous solids, good conductors of heat and electricity, that tend to form positive ions, and with a particular chemical bond that keep metal atoms in place, the metallic bond. And all of this […]

Nanothreads are one-dimensional nanomaterials composed of a primarily sp 3 hydrocarbon backbone, typically formed through the compression of small molecules to high pressures. In 2015, it was found that the slow room-temperature compression of benzene produced crystalline , one-dimensional polymers composed of diamond-like bonds. These diamondoid materials that border nanotubes and polymers are predicted to […]

An atomic state in which two spin angular momenta of electrons cancel each other, resulting in zero net spin, is called a singlet. If the angular momenta combine to give a total non-zero spin, then that state is called a triplet. A triplet state usually has lower, sometimes substantially lower, energy than a singlet. Importantly […]

Electrons do not move around nuclei in defined curved orbits. Our current understanding of how electrons are to be found in atoms and molecules is based on clouds of probability called orbitals as it is not possible to give a definite path for an electron. Thus, an orbital is a region in which an electron […]