Growing carbon nanotube or controlling its growth is a big challenge as the mechanisms of structural deformation are not fully understood. It is observed experimentally that nanotubes undergo structural deformation during growth, and it has been explained as a thermally activated process. Using quantum mechanical calculations and a simple force based analysis it is shown that (depending on growth temperature and number of dangling bonds present at the nanotube edge) both inherent structural instability and thermodynamics are responsible for the observed deformation. Moreover, it is explained how structural instability leads to differential chemical activities for the edges of carbon nanotubes. We study how such pico-level atomic interactions, evolving from the creation of dangling bonds, couples with thermal excitation. We can use such energetic interaction to module electronic states and engineer nanoscale energy transport in emerging materials with applications in bio-science and nanotechnology.