Table 4.

Atomic concentrations (%) of (a) oxygen forms, (b) nitrogen forms, (c) carbon forms, and (d) sulfur forms obtained by the fitting results of the O1s, N1s, C1s, and S2p spectra, respectively, for n-C₇ asphaltenes and resins II.

Sample	Peak
	C1s		O1s		S2p		N1s
	Assignment	%	Assignment	%	Assignment	%	Assignment	%
n-C7 Asphaltene	C–C, C–H	77.4	C–O–C, C–O	76.4	Thioether	23.4	Pyridines	40.3
	C=O	18.0	COO–	23.6	Thiophene	74.8	Pyrrolic	32.5
	COO–	4.6			Sulfones	1.8	Amines	27.3
Resin II	C–C, C-H	76.3	C-O–C, C–O	73.2	Thioether	49.5	Pyridines	63.1
	C=O	8.6	COO–	26.8	Thiophene	25.2	Pyrrolic	22.6
	COO–	15.1			Sulfones	25.3	Amines	14.3