  This paper presents a theory describing the dynamic nuclear polarization
(DNP) process associated with an arbitrary frequency swept microwave pulse. The
theory is utilized to explain the integrated solid effect (ISE) as well as the
newly discovered stretched solid effect (SSE) and adiabatic solid effect (ASE).
It is verified with experiments performed at 9.4 GHz (0.34 T) on single
crystals of naphthalene doped with pentacene-d14. It is shown that SSE and ASE
can be more efficient than ISE. Furthermore, the theory predicts that the
efficiency of the SSE improves at high magnetic fields, where the EPR linewidth
is small compared to the nuclear Larmor frequency. In addition, we show that
ISE, SSE, and ASE are based on similar physical principles and we suggest
definitions to distinguish among them.
