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Department of
Inorganic and Physical Chemistry

mno rule In the mno rule for counting skeletal electron pairs (demonstrated above), m is the number of condensed polyhedra, n is the number of polyhedral vertices, and o is the number of single-atom bridges between two polyhedra. Extra electron pairs are added for open polyhedra that have p number of vertices missing, such as the one missing vertex in each cyclopentadienyl ligand in ferrocene. The lines joining atoms outline the shape of the polyhedral structures and aren't necessarily bonds.
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Applied Theoretical and Computational Chemistry

(Should you visit us, See map to reach Rooms A101, A102, A103, IPC, 1st Floor,)
We study the structure and reactivity problems of real life molecules, clusters and solids using theoretical techniques ranging from the simplest of molecular orbital methods to sophisticated electronic structure theory depending on the system at hand and the questions that are to be answered. We place great importance in not only getting numbers as an answer to a problem, but also in finding out why the numbers turn out the way they do, based on overlap of orbitals, perturbation theory, symmetry, and in devising transferable models. Though an individual student may study specific projects in an area, there is an emphasis in the group to learn everything that goes on in the group. Regular group meetings largely achieve this.
We attempt to relate different areas of chemistry by generating models that are applicable in a variety of contexts. Often these require detailed study of apparently unrelated problems in different branches of chemistry. Relationships are then established between problems in one area to another: e.g. between organic and organometallic chemistry, amongst the chemistry of various main group elements, between allotropes of elements and their compounds and so on. A recent example involves the understanding of condensed polyhedral boranes, elemental boron and metallocenes using the newly introduced mno rule.
General Areas of Interest have been labeled for convenience at different times as Theoretical Inorganic Chemistry, Theoretical Organic Chemistry, Computational Chemistry, Transition Metal Organometallics, Electronic Structure and Electron Counting Rules, Three Dimensional Aromaticity, and, Molecular Modeling and Computational Drug Design. Current projects include Reactions of (C5H5)2Ti, (C5H5)2Zr Complexes, C-H, C-X, Si-H Bond Activation, Huckel 4n+2, Wade's n+1 and Jemmis mno Rules: Comparisons and applications, Electronic Structure of elemental boron and boron rich-solids, Boron Fullerenes and Nanotubes, Metallocene analogs with Phosphorus rings, Electronic Structure Description of Improper and anti-Hydrogen Bonds, Nickel Mediated Benzyne and Carboryne coupling with acetylenes, Stabilization of unusual coordination numbers and geometries, Cycloadditions involving fullerenes, Structure based approaches to Lead-optimization and Study of PDE-4 (Phosphodiesterase) Inhibitors, and Mechanism of alpha aminoxylation.

Representative Publications

Jorly Joseph, T. V. RajanBabu, Eluvathingal D. Jemmis,"A Theoretical Investigation of the Mechanism of Hydrovinylation Reaction", Organometallics., 28(12),3552-3566,2009.View

Susmita De, Glesni A. Pierce, Dragoslav Vidovic, Deborah L. Kays, Natalie D. Coombs, Eluvathingal D. Jemmis, and Simon Aldridge, "Reactivity of cationic terminal borylene complexes: Novel mechanisms for insertion and metathesis chemistry involving strongly Lewis acidic ligand systems", Organometallics.,28(10),2961-2975,(2009).View

Satyanarayan Sahoo, K. Hari Krishna Reddy, Rajendra S. Dhayal, Shaikh M.Mobin, V. Ramkumar, E. D. Jemmis and Sundargopal Ghosh ,"Chlorinated Hypoelectronic Dimetallaborane Clusters: Synthesis,Characterization, and Electronic Structures of (?**5**-C**5**Me**5**W)**2**B **5**H**n**Cl**m** (**n** = 7, **m** = 2 and **n** = 8, **m** =1)", Inorg.Chem.,48(14),6509-6516,2009.View

Oottikkal Shameema and Eluvathingal D. Jemmis,"Closo versus Hypercloso Metallaboranes:A DFT Study",Inorg.Chem.,48(16),7818-7827,2009.View

Amit Basak, Sanket Das, Dibyendu Mallick and Eluvathingal D. Jemmis,"Which One Is Preferred: Myers-Saito Cyclization of Ene-Yne-Allene or Garratt-Braverman Cyclization of Conjugated Bisallenic Sulfone? A Theoretical and Experimental Study", J.Am.Chem.Soc.,131(43),15695-15704,2009.View

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E. D. Jemmis

IPC Department
Indian Institute of Science
Bangalore 560 012, INDIA
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Interaction diagram between two Fe(CO)3 fragments.
B20H16, mno Rule
m = 2, n = 20 , o = 0.
m + n = 22 skeletal electron pairs; 16 electron pairs from BH and 6 from 4B.
Hence B20H16 is neutral
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