error in creating executable for python script

Question

I have created a application using python2.7 also used pyqt for gui. I have also used pybel module for computations.

my application python file works properly. but when I try to create executable from that python file it gives me error.

I have tried using py2eye, cx_freeze and pyinstaller too.

I am wondering if the python file runs well after typing "python ui_MolecularTest.py" on command prompt, why I am unable to create executable from the same?

Thanks