Normally absorption or emission of ultraviolet visible light occur in the same region. If bathochromic or hypsochromic shift occurs it should go to other regions. Normally we are not observing it. Why is it so.
You are talking about stokes shift. It occurs due to dissipation of absorbed energy due to internal conversions, vibrational relaxations, intersystem crossing etc.UV-visible region is very large region. For so large stokes shift, material need to dissipate its energy through all these non radiative pathways. In other words the band gap of the molecule has to be very small and according to Energy Gap Law, non radiative decay rate increases exponentially with decrease in band gap of molecule. So usually the energy absorbed in UV-visible region is dissipated through non radiative decay before emission goes into NIR or IR region.
However few highly conjugated materials like porphyrins, pthalocyanins, etc absorbs in visible region and have emission in NIR region.
Bathochromic or hypsochromic shift only shifts the wavelength for 2-10nm. It need not to go to other region.
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