Preventing corrosion in sour gas environments presents a serious challenge to oil producers. Corrosion inhibitors are often used in sour gas environments to prevent corrosion. In sour gas, depending upon the fugacities of carbon dioxide and hydrogen sulfide in the gas, temperature and pressure of the system, and brine chemistry, different types of iron sulfide and iron carbonate product layers are formed. Molecular modeling has previously been used in understanding the mechanism of
corrosion inhibition in carbon dioxide systems. In this work, a new force field is developed to understand mackinawite, an important iron sufide scale formed during H2S corrosion. As many authors have found the dissolution of this scale to be a rate determining step during the corrosion of iron in H2S environments. This work forms an important step in using molecular modeling techniques to study the corrosion of iron in H2S environments and its inhibition.