title: Photochemical modification of the surface area and tortuosity of a trans-1,2-bis(4-pyridyl)ethylene periodic mesoporous MCM organosilica.
abstract: A periodic mesoporous MCM-41 organosilica containing trans-1,2-bis(4-pyridyl)ethylene (t-BE) (350 m2 g-1; 0.28 cm3 g-1) incorporated in the silica walls undergoes photochemical isomerization to the cis configured bis(4-pyridyl)ethylene resulting in a dramatic area (473 m2 g-1) and pore volume (0.38 cm3 g-1) increase.