Recursive algorithm to find the determinant of a matrix

Below, i have shown the code to calculate the determinant value of a matrix.mat is the pointer to the single dimensional array everywhere and dimension is the dimension of a matrix. if 3x3 then dimension=3.
The code shows no compilation errors. But when it is run, i get an error saying some block of memory ( i dun remember which block) cannot be written.
what could possibly be the problem?

Code:

#include <stdio.h>
#include <stdlib.h>
#include <math.h>

int det_recursive(int* mat,int dimension){
	short int iter;
	int * temp_mat;
	int det_mat=0;
	for (iter=0;iter<dimension;iter++){
		temp_mat=(int *) malloc(pow(dimension-1,2)*sizeof(int));
		form_new_mat(mat,iter,temp_mat,dimension);
       det_mat=det_mat+((*(mat+iter))*det_recursive(temp_mat,dimension-1)*pow(-1,iter));
	}
	free(temp_mat+iter);
return det_mat;
}

int form_new_mat(int * mat,int iter,int * temp_mat,int dimension){
	int temp_iter=dimension;
	int new_iter=0;
	while(temp_iter<pow(dimension,2)){
		if (iter== temp_iter % dimension) temp_iter++;
		else{
			*(temp_mat+new_iter)=*(mat+temp_iter);
			new_iter++;
		}
	}
return 0;
}


int main(){
	int dimension=3;
	int mat[9]={1,0,0,0,1,0,0,0,1},i,j;
	for (i=0;i<0;i++) printf("\nhello world");
	//printf("%d",det_recursive(mat,dimension));
	system("pause");
return 0;
}

Split from dead thread Determinant Calculation Program.... HELP PLZ
Please see the forum rules.

> free(temp_mat+iter);
You're not freeing what you malloc'ed.
You can't free part of a block of memory.

Actually thats what i felt and thats what i had put in the first place. but i was getting the same error message. so i thought, since i had allocated memory in one shot, it was enough if i free it once. but for both i got the same error message.
am sorry i dun have that much patience to go through the rules. i cant read something which is really long. I am actually facing that mental problem since my childhood. I cant read text books so i listen to what my teacher is sayin. excuse me for not going through it.i am not doing it intentionally!