The surname Raskolnikov comes from raskol, a Russian word meaning split, the same word that names the Great Schism that divided the Russian Orthodox Church in the seventeenth century. The novel does not explain the name, but the idea of a man split in two runs through the character from beginning to end.
The dissenters of that schism were called raskolniki, and the book has a figure connected with that world: Porfiry describes the painter Nikolay, who confesses to a crime he did not commit, as a young man of sectarian origin who wants to suffer. The link to Raskolnikov's name, however, is a reading of the word, not a line in the text.
What the text shows are divisions. The body gives away what the head still defends; reason approves the account, and nature refuses. Razumikhin describes his friend to his mother as sometimes "cold and insensitive to the point of being inhuman," "as if two opposite characters alternated in him." One night in Part Four, Raskolnikov kisses Sonia's foot, saying "It was not before you that I bowed down, it was before all human suffering that I bowed down," and soon after speaks of "Freedom and power, and above all power!"
The division is also in the theory he writes, which splits humanity into two groups, and in what the crime does to him: he tells himself he killed the principle, but did not overstep. Whoever reads the name as a symbol sees in it the split between the man who thinks and the man who acts. It is a key to reading that the novel authorizes by what it shows, but does not declare.