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  2. Rotamers - Wikipedia

    en.wikipedia.org/wiki/Rotamers

    The two have equal free energy; neither is more stable, so neither predominates compared to the other. A negative difference in free energy means that a conformer interconverts to a thermodynamically more stable conformation, thus the equilibrium constant will always be greater than 1.

  3. Gauche effect - Wikipedia

    en.wikipedia.org/wiki/Gauche_effect

    The gauche effect is very sensitive to solvent effects, due to the large difference in polarity between the two conformers.For example, 2,3-dinitro-2,3-dimethylbutane, which in the solid state exists only in the gauche conformation, prefers the gauche conformer in benzene solution by a ratio of 79:21, but in carbon tetrachloride, it prefers the anti conformer by a ratio of 58:42. [9]

  4. Stability constants of complexes - Wikipedia

    en.wikipedia.org/wiki/Stability_constants_of...

    For example, the complex [Ni(dien) 2)] 2+ is more stable than the complex [Ni(en) 3)] 2+; both complexes are octahedral with six nitrogen atoms around the nickel ion, but dien (diethylenetriamine, 1,4,7-triazaheptane) is a tridentate ligand and en is bidentate. The number of chelate rings is one less than the number of donor atoms in the ligand.

  5. Eclipsed conformation - Wikipedia

    en.wikipedia.org/wiki/Eclipsed_conformation

    Eclipsed conformation (image right in Newman projection) Staggered conformation. In chemistry an eclipsed conformation is a conformation in which two substituents X and Y on adjacent atoms A, B are in closest proximity, implying that the torsion angle X–A–B–Y is 0°. [1]

  6. List of elements by stability of isotopes - Wikipedia

    en.wikipedia.org/wiki/List_of_elements_by...

    An even number of protons or neutrons is more stable (higher binding energy) because of pairing effects, so even–even nuclides are much more stable than odd–odd. One effect is that there are few stable odd–odd nuclides: in fact only five are stable, with another four having half-lives longer than a billion years. [citation needed]

  7. Cyclohexane conformation - Wikipedia

    en.wikipedia.org/wiki/Cyclohexane_conformation

    The chair conformation is the most stable conformer. At 298 K (25 °C), 99.99% of all molecules in a cyclohexane solution adopt this conformation. The C–C ring of the chair conformation has the same shape as the 6-membered rings in the diamond cubic lattice. [7]: 16 This can be modeled as follows.

  8. Piperidine - Wikipedia

    en.wikipedia.org/wiki/Piperidine

    After much controversy during the 1950s–1970s, the equatorial conformation was found to be more stable by 0.72 kcal/mol in the gas phase. [20] In nonpolar solvents , a range between 0.2 and 0.6 kcal/mol has been estimated, but in polar solvents the axial conformer may be more stable. [ 21 ]

  9. Argon compounds - Wikipedia

    en.wikipedia.org/wiki/Argon_compounds

    Cluster molecules containing dichlorine and more than one argon atom can be made by forcing a 95:5 mixture of helium and argon and a trace of chlorine though a nozzle. ArCl 2 exists in a T shape. Ar 2 Cl 2 has a distorted tetrahedron shape, with the two argon atoms 4.1 Å from each other, and their axis 3.9 Å from the Cl 2 .