Thermochromism reversibly intrinsic

Real organic thermochromism - reversibly intrinsic systems... 

A technically more appropriate approach is to separate reversible organic thermochromism into intrinsic systems, where heat is the sole cause of the colour change, from indirect systems, in which the colour variation involves changes in... 

A technically more appropriate approach would be to diversify the reversible organic thermochromism of intrinsic systems, in which heat is the only factor influencing the colour change, from the indirect systems in which the colour change is induced by the heat that affects the surroundings of the chromophore (Burkinshaw et al., 1999). 

Systems and molecules showing intrinsic reversible thermochromism can be classified as follows ... 

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