1 2This example illustrates how to use pw.x and ph.x to calculate 3dynamic polarizability of methane molecules (experiment stage) 4 5The calculation proceeds as follows 6 71) make a self-consistent calculation (input=ch4.scf.in, 8 output=ch4.scf.out) 9 102) make a (imaginary) frequency dependent polarizability calculation 11 (input=ch4.fpol.in, output=ch4.fpol.out). 12