No, it was not a Mind Trick. Just Palpy's manipulation.
Examples of Mind Tricks:
"You do not need to see his identification. These are not the droids you're looking for. Move along." - Obi-Wan's bypassing of the stormtroopers
*click* "What was that?" - Obi-Wan's creation of a loud distracting noise.
I don't see Palpatine doing either of those.
It was Anakin being slowly maniupliated by palps from when he was a child, thats what. thats not a mind trick, they dont work on strong minded people like Jedi.
example of a mind trick:
"Hey you wanna buy some deathsticks?"
"You dont want to sell me deathsticks.."
"I dont wanna sell you deathsticks"
"you want to go home and rethink your life"
"i want to go home and rethink my life"
well i wuldnt call it jus palpatine's manipulation
loss of mother
massacre of sand people
impatience
selfishness (he and his wife were talking in hotel room...said he wanted more power)
killing of jedi and younglings
loss of wife
irony of the loss of his wife
and then plapy manipulation
and well that about sums it up for me
Does the massacre of sand people really count? C'mon, they killed his mom--the @$$holes deserved it. I'm sure Ani loved every second of it. (I would) it's kinda hard to forgive the killer of a family member--especially a bunch of creatures that make unintelligible noises. I know that Jedi hafta respect life in any form, but still.