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  2. Urea - Wikipedia

    en.wikipedia.org/wiki/Urea

    The structure of the molecule of urea is O=C(−NH 2) 2.The urea molecule is planar when in a solid crystal because of sp 2 hybridization of the N orbitals. [8] [9] It is non-planar with C 2 symmetry when in the gas phase [10] or in aqueous solution, [9] with C–N–H and HN–H bond angles that are intermediate between the trigonal planar angle of 120° and the tetrahedral angle of 109.5°.

  3. Hydrogen bond - Wikipedia

    en.wikipedia.org/wiki/Hydrogen_bond

    The general notation for hydrogen bonding is Dn−H···Ac, where the solid line represents a polar covalent bond, and the dotted or dashed line indicates the hydrogen bond. [6] The most frequent donor and acceptor atoms are nitrogen (N), oxygen (O), and fluorine (F), due to their high electronegativity and ability to engage in stronger ...

  4. Bonding in solids - Wikipedia

    en.wikipedia.org/wiki/Bonding_in_solids

    A solid with extensive hydrogen bonding will be considered a molecular solid, yet strong hydrogen bonds can have a significant degree of covalent character. As noted above, covalent and ionic bonds form a continuum between shared and transferred electrons; covalent and weak bonds form a continuum between shared and unshared electrons.

  5. Chloramines - Wikipedia

    en.wikipedia.org/wiki/Chloramines

    N-Chloropiperidine is a rare example of an organic chloramine. [5] Chloramine-T is often referred to as a chloramine, but it is really a salt (CH 3 C 6 H 4 SO 2 NClNa) derived from a chloramine. [6] Organic chloramines feature the NCl functional group attached to an organic substituent.

  6. Non-covalent interaction - Wikipedia

    en.wikipedia.org/wiki/Non-covalent_interaction

    It is not a covalent bond, but instead is classified as a strong non-covalent interaction. It is responsible for why water is a liquid at room temperature and not a gas (given water's low molecular weight). Most commonly, the strength of hydrogen bonds lies between 0–4 kcal/mol, but can sometimes be as strong as 40 kcal/mol [3] In solvents ...

  7. Ammonia borane - Wikipedia

    en.wikipedia.org/wiki/Ammonia_borane

    The B−N distance is 1.58(2) Å. The B−H and NH distances are 1.15 and 0.96 Å, respectively. Its similarity to ethane is tenuous since ammonia borane is a solid and ethane is a gas: their melting points differing by 284 °C. This difference is consistent with the highly polar nature of ammonia borane.

  8. Chemical bond - Wikipedia

    en.wikipedia.org/wiki/Chemical_bond

    Hydrogen bonds of the form A--H•••B occur when A and B are two highly electronegative atoms (usually N, O or F) such that A forms a highly polar covalent bond with H so that H has a partial positive charge, and B has a lone pair of electrons which is attracted to this partial positive charge and forms a hydrogen bond. [23]: 702 Hydrogen ...

  9. Cation–π interaction - Wikipedia

    en.wikipedia.org/wiki/Cation–π_interaction

    Bonding energies are significant, with solution-phase values falling within the same order of magnitude as hydrogen bonds and salt bridges. Similar to these other non-covalent bonds, cation–π interactions play an important role in nature, particularly in protein structure, molecular recognition and enzyme catalysis. The effect has also been ...