Tuesday, November 6, 2012

Bent Bond

                       Bent bonds are also known as banana bond. sterically hindered molecules whose binding orbitals are forced into a banana like form. Bent bonds are often more susceptible to reaction than ordinary bonds.

  Cyclopropane  ( C3H6 )

3c- 4e Bond

                               The 3 center 4 electron bond is a a model used to explain in hypervalent molecules such as phosphorus pentafluoride, sulfur hexafluoride ane xenon fluorides. It is also known as Pi mentel - Rundle three center model.

Quadruple Bond

                          A quqdruple bond is a type of chemical bond between two atoms involving 8 electrons. This bond is an existension of the more familiar types double bond and triple bond. Stable quatruple bonds are most common among the transition metal , in the middle of the d block such as tungsten and chromium. Typically the ligands that support quadruple bonds are pi donors . not in pi acceptors.
                         Valence bond theory predicts a quatruple bond as the only way to satisfy the octet rule for carbon in dicarbon. However MOT shows that three are two sets of paired electrons in the sigma system. (one bonding and one anti bonding)  and two sets of paired electrons in a degenerate pi bonding set of orbitals. This adds up to give a bond order of 2 , meaning that three exist a double bond between the 2 carbon in a C2 molecule. This is surprising because the MO diagram of diatomic carbon would show that three are 2 pi bonds and no sigma bonds.

Triple Bond

                    A covalent bond formed between three atoms by the mutual sharing of three electron pairs is called Triple bond. Triple bonds are denoted as three lines in chemical structure diagram. Triple bonds are stronger than single bonds or double bonds and they are also shorter. The bond order is three.



Double Bond

                        A covalent bond formed between two atoms by the mutual sharing of two electron pairs is called double bond.Double bonds are drawn as two parallel lines in chemical structure diagrams. Double bonds are shorter than single bond.The bond order is two.Double bonds are also electron rich , which makes them reactive.

           Ethylene (C2H4) is a hydrocarbon with a double bond between the two carbon atoms.