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Chemistry Forums for Students => Physical Chemistry Forum => Topic started by: kunig on January 26, 2015, 11:19:44 AM

Title: Problem Of Charge
Post by: kunig on January 26, 2015, 11:19:44 AM
Hello,
I want to optimize a molecule with gaussian 03 before and after deprotonation of two groups (COOH) in the molecule.
So, i want to ask if i have to change the total charge of molecule to (-2) after the deprotonation (2COO-).
Thank you 
Title: Re: Problem Of Charge
Post by: Irlanur on January 26, 2015, 02:31:50 PM
Well yes? or do you include the protons?
Title: Re: Problem Of Charge
Post by: kunig on January 26, 2015, 03:20:30 PM
Well yes? or do you include the protons?

Hello, thank you for replying
The molecule contain two groups (COOH), the total charge is 0
i want to make a deprotonation of the two groups (COOH) (2COOH -2H+ to obtain 2COO-). So in the new structure with two groups (COO-), when i define the charge in the gaussian 03 program , i will put -2 ? is that correct ?
Thanks in advance. 
Title: Re: Problem Of Charge
Post by: Irlanur on January 26, 2015, 03:43:58 PM
of course... what else?
Title: Re: Problem Of Charge
Post by: kunig on January 26, 2015, 03:48:45 PM
of course... what else?

Ok Thank you :)