Virtual education has grown exponentially in the past year due to the global COVID19 pandemic. In this context, the exploration of teachers' perceptions of their students' emotions when using ICTs has become more relevant. The aim of this study was two-fold, on the one hand, to analyze how teachers perceived their students' emotions and, on the other hand, to analyze the emotions teachers wanted to modulate in their students when using ICTs. To this end, an interpretative and comparative study was implemented using the Lexical Availability technique. The sample was formed by 178 Chilean teachers who took a lexical availability test. The analysis included general vocabulary through network graphs and a comparison across gender, academic background, school type and knowledge area. The results made it possible to identify the latent mental lexicon of teachers, revealing significant differences in the perception of emotions, according to gender and ICTs use and according to gender and knowledge area. The study further projects the potential of lexical availability to determine the emotions required by Affective Informatics in the adaptability of educational systems and to make adjustments to the instructional design.