Dr Chandrika Varadachari is an interdisciplinary scientist working in the interfaces of chemistry with Earth Science, Environmental Science and Material Science.  Her research is fusion of several disciplines of applied sciences and technology mostly in the geology-mathematics-thermodynamics and technology-chemistry-agriculture interfaces and  materials modelling and design.

Dr Varadachari’s PhD thesis was on the development of processes for the conversion of waste micas into potash fertilizers. She successfully developed unique processes for utilisation of muscovite wastes for producing potassium phosphates. Biotite mica (black mica) which has no commercial utility at present, was converted to potassium sulphate (a high value fertilizer), ammonium alum and pure silica. The process was subsequently upgraded to a pilot level

Dr Varadachari later pioneered the development of a new category of slow-release fertilizers, now termed bio-release fertilizers. These compounds, which contain various micronutrient ions, are not only water insoluble but also completely bio-available (unlike all previous slow-release fertilizers). The bio-release fertilizers are non-leachable and non-polluting; yet they contain nutrients in a chemical form that is extractable by plant roots.

Studies on clay-humus complexes lead to the development of a comprehensive picture of interactions of soil minerals with organic substances. These concepts have been developed based on an in-depth study of crystal structures, chemical reactions and high precision analytical data.

Dr Varadachari has incorporated new thermodynamic concepts and non-conventional mathematics to understand the behaviour of mineral systems. This has resulted in improved perceptions of phase equilibria and a new methodology for defining variable composition minerals by fuzzy mathematics and a very novel method for derivation of graded phase diagrams incorporating fuzzy logic.

New fields of study currently undertaken are on the applications of thermodynamics and quantum mechanics for virtual design of ceramics. Another area that Dr Varadachari is now working on is the use of ab initio methods for modelling abiotic polymerisation of biological macromolecules  to understand the origin of life on Earth.

Doctorate students & their thesis:

1. Dr Sanjay Ray : Novel slow-releasing micronutrient fertilizers :Formulation, synthesis and applicability.

2. Dr Ajijul H Mondal : Some aspects of clay-humus formation.

3. Dr Md Kudrat : Mineral equilibria in silicate systems.

4. Dr Hasmot Saikh : Effect of deforestation and cultivation on some soil chemical properties.

5. Dr Tarit Chattopadhyay : Investigations on the complexes of humic substances with some inorganic soil components.

6. Dr Sanjib Kar : Ion binding in soil humic substances.

7. Dr Partha K Chandra : Polyphosphate based micronutrient fertilizers.

8. Dr Nayan Ahmed : Studies on naturally occurring clay-humus complexes.

9. Dr Gautam Goswami : Studies on oxides and hydrous oxides of iron.

10. Ms Ishita Bhattacharya

11. Ms Gargi Mukherjee

12. Ms Sruti Das

13. Mr Shiladitya Bandopadyay

Awards received :

• INSA (Indian National Science Academy) Young Scientist Award

             First recipient from Agricultural Chemistry and/or Soil Science.

• DST (Department of Science & Technology, Government of India)

            Young Scientist (1988).  Second recipient from West Bengal.

• UNESCO-ROSTSCA Award (1990) in Chemistry.      

• Calcutta University Gold Medalist.

• Fellow and (at present) Sectional Committee Member,

            West Bengal Academy of Science & Technology, Calcutta   

Projects : Dr Varadachari has conducted eleven sponsored research projects as the Principal Investigator

A few research publications :

(1)    Development of a Novel Slow-Releasing Iron-Manganese Fertilizer Compound. I. Bhattacharya, S.Bandyopadhyay, C Varadachari  and  K Ghosh : Industrial & Engineering Chemistry Research : 46 : 2870-2676  

(2)  Fuzzy phase diagrams of clay minerals : Varadachari C : Clays & Clay Minerals : 54 616-625 (2006)

 (3)  Discriminant analysis of clay mineral compositions : C. Varadachari & G. Mukherjee : Clays & Clay Minerals : 52 311-320, (2004).

 (4) Varadachari C, Mukherjee G,  Goswami D P  and Chakraborty M K (2003) Understanding clay minerals with fuzzy mathematics, Naturwissenschaften  90  44-48.

 (5)  Application of the improved regression method to derive DG⁰_f of non-stoichiometric clay minerals and their correlations with compositional parameters : M. Kudrat, C. Varadachari & K. Ghosh : Chemical Geology (Netherlands) : 168 : 225-238 (2000).

 (6)  An algorithm and program in C language for computation of standard free energy of formation of clay minerals : M. Kudrat, K.P. Sharma, C. Varadachari  & K. Ghosh : Computers & Geosciences (UK) 25 : 241-250 (1999).

 (7)  Evaluation  of  standard  free  energies  of  formation  of  clay  minerals by an improved regression method : C. Varadachari, M. Kudrat & K. Ghosh : Clays & Clay Minerals (USA) 42 : 298-307 (1994).

(8)  Constructing  phase  diagrams  for  silicate  minerals  in  equilibrium with an  aqueous phase : A theoretical approach : C. Varadachari : Soil Science (USA) 153 : 5-12 (1992).

(9)    Saikh H, Varadachari C and Ghosh K (1998) Changes  in  carbon, nitrogen and phosphorus levels due to deforestation and cultivation : A case study in Simlipal National Park, India, Plant & Soil   198 137-145. 

(10)   Ray S K, Varadachari C and Ghosh K (1997) Novel  slow-releasing  micronutrient  fertilizers 2. Copper Compounds, Journal of Agricultural &  Food Chemistry   45 1447-1453.

(11)    Varadachari C, Kudrat M and Ghosh K (1994) Evaluation  of  standard  free  energies  of  formation  of  clay  minerals by an improved regression method, Clays & Clay Minerals   42 : 298-307.

(12)    Varadachari C, Mondal A H, Nayak D C and Ghosh K (1994) Clay-humus complexation : Effect  of   pH  and  the  nature of   bonding, Soil Biology & Biochemistry   26 : 1145-1149.

(13)    Ray S K, Varadachari C and Ghosh K (1993) Novel slow-releasing micronutrient fertilizers. I. Zinc compounds, Industrial & Engineering Chemistry Research  32 1218-1227

(14)    Varadachari C (1992) An investigation on  the reaction of  phosphoric acid   with  mica  at elevated temperatures, Industrial & Engineering Chemistry Research  31 357-364

(15)    Barman A K, Varadachari C and Ghosh K (1992) Weathering  of   silicate  minerals  by   organic  acids   :   I.  Nature  of  cation solubilisation, Geoderma  53 : 45-63.

(16)    Varadachari C, Mondal A H and Ghosh K (1991) Some  aspects of  clay-humus  complexation :  Effect of exchangeable cations and lattice charge, Soil Science  151 : 220-227.

(17)Nayak D C, Varadachari C and Ghosh K (1990) Influence  of   organic  acidic   functional    groups  of   humic substances in complexation with clay minerals, Soil Science   149 : 268-271.