EIS data of C-steel in 1 M HCl and in the presence of altered doses of the investigated inhibitors (I & II) at 25 °C.

Comp.	Conc., M	C dl, μF cm−2	R ct, Ω cm2	n	θ	IE%	χ 2
1 M HCl	00	117.9 ± 0.2333	31.8 ± 0.1764	0.84 ± 0.01	—	—	0.002
Inhibitor (I)	1 × 10−6	93.7 ± 0.2145	51.6 ± 0.1453	0.85 ± 0.02	0.386	38.6	0.004
	5 × 10−5	88.9 ± 0.1453	81.6 ± 0.2028	0.85 ± 0.02	0.613	61.3	0.003
	9 × 10−5	81.2 ± 0.1732	134.1 ± 0.2309	0.87 ± 0.01	0.764	76.4	0.005
	13 × 10−5	78.9 ± 0.1245	178.3 ± 0.1732	0.86 ± 0.01	0.822	82.2	0.001
	17 × 10−5	63.6 ± 0.1178	197.3 ± 0.2028	0.87 ± 0.02	0.839	83.9	0.006
	21 × 10−5	61.7 ± 0.1714	244 ± 0.1453	0.88 ± 0.03	0.870	87.0	0.007
Inhibitor (II)	1 × 10−6	91.4 ± 0.1412	74.3 ± 0.1241	0.90 ± 0.01	0.572	57.2	0.002
	5 × 10−5	86.3 ± 0.1453	110.9 ± 0.1653	0.91 ± 0.01	0.715	71.5	0.003
	9 × 10−5	79.6 ± 0.2333	168.4 ± 0.1012	0.92 ± 0.01	0.812	81.2	0.001
	13 × 10−5	73.1 ± 0.1453	219.6 ± 0.1893	0.92 ± 0.01	0.856	85.6	0.004
	17 × 10−5	64.9 ± 0.1202	330.4 ± 0.1987	0.93 ± 0.01	0.904	90.4	0.007
	21 × 10−5	57.6 ± 0.1553	364.3 ± 0.1453	0.95 ± 0.01	0.913	91.3	0.006