Spontaneous deposition of amphiphilic porphyrin films on glassElectronic supplementary information (ESI) available: detailed kinetic studies and procedures, and aggregation studies on 1H2and 2H2. See http://www.rsc.org/suppdata/nj/b4/b403591g/

Spontaneous deposition of aggregates of a tetraphenylporphyrin derivative, possessing a cationic appended functionality, straightforwardly occurs from aqueous solutions. Combined spectroscopic studies and AFM morphological characterisation reveal that these layered films feature a consistent degree of order. Deposition of the related manganese or cobalt derivatives analogously occurs and the UV-visible spectral pattern of the films dramatically changes upon exposure to vapours of amines or olefins. This aspect can be of great importance for the construction of solid state chemical sensors.