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Symbols, Terminology, and Nomenclature
Published in W. M. Haynes, David R. Lide, Thomas J. Bruno, CRC Handbook of Chemistry and Physics, 2016
W. M. Haynes, David R. Lide, Thomas J. Bruno
where is the wavefunction, V is the potential energy expressed as a function of the spatial coordinates, E is an energy eigenvalue, 2 is the Laplacian operator, is Planck's constant divided by 2, and m is the mass. Second (s)* - The SI base unit of time. [1] Second radiation constant (c2)* - See First radiation constant. Secondary ion mass spectroscopy (SIMS) - See Techniques for Materials Characterization, page 12-1. Seebeck effect - The development of a potential difference in a circuit where two different metals or semiconductors are joined and their junctions maintained at different temperatures. It is the basis of the thermocouple. Selenides - Compounds having the structure RSeR (R not equal to H). They are thus selenium analogues of ethers. Also used for metal salts of H2Se. [5] Semicarbazones - Compounds having the structure R2C=NNHC(=O)NH2, formally derived by condensation of aldehydes or ketones with semicarbazide [NH2NHC(=O)NH2]. [5] Semiconductor - A material in which the highest occupied energy band (valence band) is completely filled with electrons at T = 0 K, and the energy gap to the next highest band (conduction band) ranges from 0 to 4 or 5 eV. With increasing temperature electrons are excited into the conduction band, leading to an increase in the electrical conductivity. Semiquinones - Radical anions having the structure -O-Z-O where Z is an ortho- or para-arylene group or analogous heteroarylene group; they are formally generated by the addition of an electron to a quinone. [5] SI units* - The International System of Units adopted in 1960 and recommended for use in all scientific and technical fields. [1] Siemens (S)* - The SI unit of electric conductance, equal to -1. [1] Sievert (Sv)* - The SI unit of dose equivalent (of radiation), equal to J/kg. [1] Silanes - Saturated silicon hydrides, analogues of the alkanes; i.e., compounds of the general formula SinH2n+2. Silanes may be subdivided into silane, oligosilanes, and polysilanes. Hydrocarbyl derivatives are often referred to loosely as silanes. [5] Silicones - Polymeric or oligomeric siloxanes, usually considered unbranched, of general formula [-OSiR2-]n (R not equal to H). [5] Siloxanes - Saturated silicon-oxygen hydrides with unbranched or branched chains of alternating silicon and oxygen atoms (each silicon atom is separated from its nearest silicon neighbors by single oxygen atoms). [5] Skin effect - The concentration of high frequency alternating currents near the surface of a conductor. Slater orbital - A particular mathematical expression for the radial part of the wave function of a single electron, which is used in quantum-mechanical calculations of the energy and other properties of atoms and molecules. Small angle neutron scattering (SANS) - See Techniques for Materials Characterization, page 12-1. Snell's law - The relation between the angle of incidence i and the angle of refraction r of a light beam which passes from a medium of refractive index n0 to a medium of index n1, viz., sin i/sin r = n1/n0. Solar constant* - The mean radiant energy flux from the sun on a unit surface normal to the direction of the rays at the mean
Novel ((E)-((2-hydroxynaphthalen-1-yl)methylidene)amino)urea ligand and its Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) complexes: Synthesis, characterization, molecular docking, and anti-cancer activities
Published in Inorganic and Nano-Metal Chemistry, 2023
Najlaa S. Al-Radadi, Mohammed M. El-Gamil, Mostafa A. Hussien, H. M. Salama
Semicarbazones have several donor atoms so that they can show the properties of ligands.[1] This versatile nature of heterocyclic semicarbazones makes them more interesting to study.[2] They are flexible, tending to coordinate both in ordinary and deprotonated forms due to the formation of keto-enol tautomerism.[3–6] The biological and chemical potency of semicarbazones results from the trigonally hybridized lone pair of the nitrogen atom of the azomethine group.[7,8] The coordination ability of semicarbazones steers us to identify the biological properties of ligand and metal complexes. The complex can come up to be more potent than the free ligand.[9–12] The derivatives of semicarbazones can be found to be effective pharmaceutically and biologically such as tumor growth inhibition,[13,14] antimicrobial,[14–16] and DNA-binding.[14,17] Furthermore, Cu(II) complexes demonstrated strong cytotoxic efficacy toward cancer cell lines, antioxidant activities,[18] and DNA binding ability.[19–21]
Review: Schiff base metal complexes as anti-inflammatory agents
Published in Journal of Coordination Chemistry, 2023
Qurat-Ul-Ain Sandhu, Muhammad Pervaiz, Abdul Majid, Umer Younas, Zohaib Saeed, Adnan Ashraf, Rana Rashad Mahmood Khan, Sami Ullah, Faisal Ali, Seemal Jelani
These ligands appeared in 1800 and later proved as good chelating agents [5]. Semicarbazones/thiosemicarbazones have been prepared by condensation of carbonyl compounds and semicarbazide or thiosemicarbazide. Semicarbazones/thiosemicarbazones have various donor atoms and are tridentate. These ligands are important because of their lipophilic nature and chelating ability.