“…A vast amount of studies was published concerning crystalline-amorphous (c-a) interfaces of different, mostly tetrahedrally coordinated materials, including c-Ge=a-Ge [1], c-Si=a-Ge [2,3], c-Si=a-Si [1,[4][5][6][7], c-Al 2 O 3 =a-CaSiO 3 [8], c--Si 3 N 4 =a-SiO 2 [9], and c-Si=a-SiO 2 [10][11][12][13][14][15][16][17][18][19][20][21], the last example being an important interface in semiconductor technology. The transitional structures were investigated by a large variety of theoretical [1,4,6,8,14,16,17,19] and experimental methods [2,3,5,[9][10][11][12][13]15,18,20,21]. However, the interface between crystalline and vitreous silica has not been addressed so far.…”