“…Recently, in addition to ‘classical’ 1-crowdion, the so-called N -, M -, and -crowdions have been intensively studied [ 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 ]. In the first case, the initial momentum is imparted to N neighboring atoms located in the same close-packed row along the row; in the second case, to a group of atoms in M neighboring atomic rows; and in the third case, to block of atoms.…”