Can we get admission in to IIT PhD chemistry, by clearing GATE and NET?

 I am a PhD graduate from one of the IITs, so I think, I am eligible to answer this question.

In one line the answer is - YES, you can get into IITs to do PhD even only via GATE. 

After MSc, you can enter into IITs to do PhD without even qualifying JRF. You don't need to qualify NET to enter into PhD in IIT.

You can even enter IIT to do a PhD without having both NET and GATE. If you have JEST or INSPIRE fellowship, you can get admission to IIT after your MSc in Chemistry to do a PhD.

Every year GATE exam is conducted by either one of the IITs and IISc in various subjects. First of all, you need to qualify for this exam, and in addition, you need to have good ranks under 1000 for Chemistry and basic sciences so that you have a high chance of being called for an interview. 

If you have qualified CSIR/UGC-NET, then you are in an advantageous position as professors generally have more vacancies for CSIR students compared to GATE students. Nevertheless, whether you have cleared GATE/NET or both or anything else, you need to do well in the interview to get admission.

For Chemistry: If you have only GATE in Chemistry, you need to perform well in interview which will be mostly subsectioned into Physical, Organic and Inorganic Chemistry, so opt for the one in which you want to do your PhD and you are most comfortable. Brush up your basics very well up to MSc level and appear for the interview. You are not supposed to know everything, but you should try to solve every problem they give you. The answer often does not matter, what matters is your approach.

Do carry your MSc project report and publication (if any) with you in the interview hall. Some questions may also be asked from your project.

If you are from the Physical Chemistry branch (whether experimental/theoretical), do prepare this topic well -

1. Basics of group theory, if given a character table, you should be able to tell IR/Raman active vibrations.

2. Mathematical equations and their drawings, e.g. they may ask you to draw, y=exp(-x), y=exp(-x2), y=xexp(-x2)

3. Particle in a box and operators, basics of quantum mechanics.

4. Basics of solid state chemistry and Chemical Kinetics along with Enzyme catalysis.

5. Thermodynamics - here the concepts need to be understood very well because interviewers often ask in this topic and go very deep into the topic.

6. Basics of electrochemistry

So, all the best for your admission in IITs as a PhD scholar. Feel free to comment if you have any doubt. Have a great day!