Geant4 is a general purpose and open source C + + Monte Carlo simulation toolkit, widely used in the scientific community. It is able to simulate physical interactions of particles through matter. According to the user's needs, models for the simulation of electromagnetic (EM) interactions are provided in two Geant4 subpackages, the 'standard' EM subpackage, well suited for a wide range of applications and the 'low-energy' EM subpackage, able to reach the electronVolt regime. Particle-induced X-ray emission (PIXE) is a well known and a very useful technique for quantitative elemental analysis in environmental, archaeological, biological, medical and space applications. An atomic de-excitation module is part of the Geant4 'low-energy' EM subpackage since 1999 and has been validated in recent years. PIXE simulation has been included in this subpackage in 2001 and new ionisation cross-sectional models following the ECPSSR theory have been added for the PIXE simulation in 2008. In 2010, these models have been further extended to higher energies. In this work, we present new results on the verification of these models and an overview of the new interface to PIXE modelling prepared for the recent public release of the Geant4 toolkit (December 2010) allowing a unified usage of the Geant4 de-excitation module by both 'standard' and 'low-energy' subpackages. Copyright © 2011 John Wiley & Sons, Ltd.Read less <