[Og]

Hi ,
I'm looking for a substance that glow when react with water, or "touching" water.
Does anyone know such a substance ?
I prefer that this substance will not be consumed by the reaction.
Thanks so much
Og

[Arkcon]

That is going to be a little difficult.  Water has a oxygen atom with an unpaired electron.  That makes it a good molecule for "stealing" the extra energy another atom's electron's may have -- energy that the atom might try to dump as light energy.  We consider water a good "quencher" for luminescence and fluorescence, for that reason.

Of course, I have been wrong on this subject before: http://www.chemicalforums.com/index.php?topic=56716.msg204430#msg204430  But from what I know of luminescence and fluorescence, these are pretty difficult reactions to achieve.  I can only think of a few.  But lately, everyone seems to want a blast of light from the very simplest of chemicals. For example:  http://www.chemicalforums.com/index.php?topic=56602.msg204053#msg204053  And I feel I'd be wasting everyone's time if I didn't warn people how unlikely that is.

[Og]

Hi Arkcon ,
Thanks so much.
I also went through these thoughts and hoped to hear something else.
But as you pointed out , it seems bit too much
I'll appreciate if anyone has any other thoughts.
Again , thank you Arkcon
Og

[Wastrel]

If visible fluorescence is all that is needed then all you want is the right water soluble dye and a UV lamp.  For a chemiluminescent solution you could use a freeze dried luciferin/luciferase/ATP mix or a luminol/catalyst/perborate powder but these involve loss.

For light to be emitted energy has to come from somewhere and for visible light you need between, what, 170kj/mol and 300kj/mol?  Reversible stores of energy that dense are fairly limited.  Crystalloluminescence is worth a look but it's almost the opposite of what is being asked.

[Og]

Hi Watrel,
Thank you for the good Ideas.
The Crystalloluminescence sound quite intresting, and I will try to further investigate in this field.
Thanks again
Og