Here we examine the evolution of irradiated clouds using the Smoothed Particle Hydrodynamics ({small SPH}) algorithm coupled with a ray-tracing scheme that calculates the position of the ionisation-front at each timestep. We present results from simulations performed for three choices of {small IR}-flux spanning the range of fluxes emitted by a typical {small B}-type star to a cluster of {small OB}-type stars. The extent of photo-ablation, of course, depends on the strength of the incident flux and a strong flux of {small IR} severely ablates a {small MC}. Consequently, the first star-formation sites appear in the dense shocked layer along the edges of the irradiated cloud. Radiation-induced turbulence readily generates dense filamentary structure within the photo-ablated cloud although several new star-forming sites also appear in some of the densest regions at the junctions of these filaments. Prevalent physical conditions within a {small MC} play a crucial role in determining the mode, i.e., filamentary as compared to isolated pockets, of star-formation, the timescale on which stars form and the distribution of stellar masses. The probability density functions ({small PDF}s) derived for irradiated clouds in this study are intriguing due to their resemblance with those presented in a recent census of irradiated {small MC}s. Furthermore, irrespective of the nature of turbulence, the protostellar mass-functions({small MF}s) derived in this study follow a power-law distribution. When turbulence within the cloud is driven by a relatively strong flux of {small IR} such as that emitted by a massive {small O}-type star or a cluster of such stars, the {small MF} approaches the canonical form due to Salpeter, and even turns-over for protostellar masses smaller than $sim$0.2 M$_{odot}$.
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