Water is a simple molecule — two hydrogens attached to one oxygen.
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In the same way, cells are incredibly complex, but it's all chemical compounds doing their thing, very simple molecule-to-molecule interactions, repeated countless times, doing remarkable things.
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A second paper in Science adds wrinkles in the Martian puzzle of methane — a simple molecule of one carbon and four hydrogen atoms — that could also play an important part in figuring out whether life ever arose there and might even persist underground today.
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Opiorphin is an endogenous chemical compound first isolated from human saliva. Initial research with mice shows the compound has a painkilling effect greater than that of morphine. It works by stopping the normal breakup of enkephalins, natural pain-killing opioids in the spinal cord. It is a relatively simple molecule consisting of a five-amino acid polypeptide, Gln-Arg-Phe-Ser-Arg.
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Production of SO as a reagent in organic syntheses has centred on using compounds that "extrude" SO. Examples include the decomposition of the relatively simple molecule ethylene episulfoxide: as well as more complex examples, such as a trisulfide oxide, C10H6S3O. :C2H4SO → C2H4 \+ SO The SO molecule is thermodynamically unstable, converting initially to S2O2. SO inserts into alkenes, alkynes and dienes producing thiiranes, molecules with three-membered rings containing sulfur.
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To begin to generate an isolobal fragment, the molecule needs to follow certain criteria. Molecules based around main group elements should satisfy the octet rule when all bonding and nonbonding molecular orbitals (MOs) are filled and all antibonding MOs are empty. For example, methane is a simple molecule from which to form a main group fragment. The removal of a hydrogen atom from methane generates a methyl radical.
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The origin of J-coupling can be visualized by a vector model for a simple molecule such as hydrogen fluoride (HF). In HF, the two nuclei have spin . Four states are possible, depending on the relative alignment of the H and F nuclear spins with the external magnetic field. The selection rules of NMR spectroscopy dictate that ΔI = 1, which means that a given photon (in the radio frequency range) can affect ("flip") only one of the two nuclear spins.
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Buckminsterfullerene (formula: C60) is an atomic cluster. In chemistry, an atom cluster (or simply cluster) is an ensemble of bound atoms or molecules that is intermediate in size between a simple molecule and a nanoparticle; that is, up to a few nanometers (nm) in diameter. The term microcluster may be used for ensembles with up to couple dozen atoms. Clusters with a definite number and type of atoms in a specific arrangement are often considered a specific chemical compound and are studied as such.
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The ethynyl radical (systematically named λ3-ethyne and hydridodicarbon(C—C)) is an organic compound with the chemical formula C≡CH (also written [CCH] or ). It is a simple molecule that does not occur naturally on Earth but is abundant in the interstellar medium. It was first observed by electron spin resonance isolated in a solid argon matrix at liquid helium temperatures in 1963 by Cochran and coworkers at the Johns Hopkins Applied Physics Laboratory. It was first observed in the gas phase by Tucker and coworkers in November 1973 toward the Orion Nebula, using the NRAO 11-meter radio telescope.
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The two spheres were then firmly held together by a metal rod inserted into the pair of opposing bushing (with fastening by screws). The models also had special features to allow representation of hydrogen bonds.In the same paper Corey and Pauling also briefly describe a much simpler but less accurate type of model, with rubber-like polyvinyl plastic spheres in the scale 1 inch = 2Å and connected by snap fasteners. See Corey & Pauling, 1953, op. cit. An example of a 3D, space-filling model of a simple molecule, sulfur dioxide, SO2, showing the electrostatic potential surface, computed for the molecule using the Spartan software suite of computational chemistry tools.
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A CN star has unusually strong cyanogen bands in its spectrum compared to other stars of its stellar class. Cyanogen is a simple molecule of one carbon atom and one nitrogen atom, with absorption bands around wavelengths 388.9 and . This group of stars was first noticed in certain G and K-type giants by J. J. Nassau and W. W. Morgan in 1949, then a further 4,150 were identified by Nancy G. Roman in 1952. They can be distinguished from barium stars by the lack of s-process elements, and from other types of luminous stars by the general weakness of features other than the CN lines.
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Aside from having its J = 1→0 transition in a clear portion of the atmospheric window, as well as having numerous isotopomers also available for easy study, and in addition to having a large dipole moment that makes observations particularly simple, HNC is, in its molecular nature, a quite simple molecule. This makes the study of the reaction pathways that lead to its formation and destruction a good means of obtaining insight to the workings of these reactions in space. Furthermore, the study of the tautomerization of HNC to HCN (and vice versa), which has been studied extensively, has been suggested as a model by which more complicated isomerization reactions can be studied.
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