Small robust organic molecules showing solidstate luminescence are promising candidates foro ptoelectronic materials. Herein, we investigate as eries of diphenylphosphanyl anthracenes [9-PPh 2-10-R-(C 14 H 8)] and their sulfur oxidised analogues.T he oxidation causes drastic changes in the molecular structurea st he new orientation of the bulky (S)PPh 2 substituent inducesastrongb utterfly bent structure of the anthracenec ore, which triggersastrong bathochromic shift resulting in ag reen solid-state fluorescence. As the emission properties changeo nly slightly upon aggregation the origin of the emission is attributed to at ypical monomer fluorescence. The host-guest complexes of [9-(S)PPh 2-10-Ethyl-(C 14 H 8)] with four basic arenes reveal an emissione nhancement up to five-times higherq uantum yields comparedt ot he pure host. Less interchromophoric interactions and ar estriction of intramolecular motion within the hostm olecules due to fixation by weak CÀH•••p interactions with the co-crystallised arene are responsible for that emission enhancement.