Parameters obtained from the fitting of experimental data of total ac conductivity with overlapping large polaron tunneling (OLPT) model for the studied sample.

Frequencies (Hz)	N(EF) (eV−1 cm−3)	α (Å−1)	W H0 (eV)	r p (Å)
501	3.83 × 1013	1	0.90	0.20
1955	4.00 × 1013	1	0.97	0.39
2511	4.37 × 1013	1	0.99	0.46
3162	4.53 × 1013	1	1.0 3	0.49