Tetragonal Cr4+ centers (3d2 electron configuration, spin S=1) in the Li2CaSiO4 crystal at different frequencies were detected and studied. The value of splitting at a zero magnetic field was determined. In the area where the positions of the two Cr4+ transitions coincide, the additional signal with inverse phase was observed. For uncontrolled impurity Mn2+ ions (S=I=5/2) the spin Hamiltonian parameters and localization are determined