Molecular clusters of two acidic species, H2SO4 and HNO3, were investigated using ab initio methods to observe intermolecular interactions. Geometric optimizations were conducted at the MP2 level using aug-cc-pVDZ and aug-cc-pVTZ basis sets. Eleven different stable geometries were detected on the intermolecular potential energy surface. Two main theories, atoms in molecules (AIM) and non-covalent interactions (NCI), were used to analyze the nature of hydrogen bonds in the H2SO4 center dot center dot center dot HNO3 system. Theresults are discussed in terms of structural, energetic, spectroscopic and topological perspectives. (C) 2017 Elsevier B.V. All rights reserved.