Table 2.

EIS parameters for the carbon steel in 1.0 M HCl in the absence and presence of different concentrations of the inhibitor compounds.

Inhibitor	Conc. (M)	Rs (Ω cm2)	Rct (Ω cm2)	Q (μ Ω–1 sn cm–2)	n	Cdl (μF cm–2)	Chi squared (χ2)	S	α°	θ	ηz %
Blank	–	4.699	91.21	1215.00	0.8632	857.368	3.34 × 10–3	− 0.572	− 55.20	–	–
DHSiMF	5 × 10–6	2.562	552	214.10	0.7165	91.971	9.89 × 10–3	− 0.640	− 56.79	0.835	83.48
	1 × 10–4	2.205	640.5	363.90	0.6297	154.538	1.76 × 10–2	− 0.570	− 51.29	0.858	85.76
	1 × 10–3	3.021	683.2	102.60	0.7777	47.995	8.87 × 10–3	− 0.701	− 63.75	0.866	86.65
	5 × 10–3	2.551	1183	105.40	0.7679	56.176	7.49 × 10–3	− 0.716	− 62.80	0.923	92.29
	1 × 10–2	2.816	3126	52.29	0.8024	33.474	6.95 × 10–3	− 0.770	− 66.78	0.971	97.08
DHSiB	5 × 10–6	2.626	468.4	341.70	0.674	140.852	1.13 × 10–2	− 0.573	− 52.08	0.805	80.53
	1 × 10–4	3.126	606.1	128.40	0.7774	61.808	6.26 × 10–3	− 0.676	− 60.57	0.850	84.95
	1 × 10–3	2.753	666	151.20	0.7697	76.076	8.38 × 10–3	− 0.671	62.10	0.863	86.30
	5 × 10–3	3.172	1059	469.60	0.5975	293.334	1.71 × 10–2	− 0.460	51.48	0.914	91.39
	1 × 10–2	2.953	1735	82.85	0.7818	48.214	5.82 × 10–3	− 0.724	− 65.67	0.947	94.74