Đang chuẩn bị liên kết để tải về tài liệu:
Carbon Alloys part 2

Tham khảo tài liệu 'carbon alloys part 2', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Hybrid Orbital Control in Carbon Alloys 19 Fig. 2.sp hybridization. The shading denotes the positive amplitude of the wave function. 12s 2p. is elongated in the positive direction of.r. negative direction of X. Thus when nearest-neighbor atoms are in the direction of the X axis the overlap of xpj with the wave function at X 0 becomes larger compared with the original 2p function so giving rise to a larger binding energy. If 12pv for 12px is selected the wave function shows a valence in the direction of they axis. It is important to emphasize that the solution of Eq. 3 is not a unique solution of Eq. 2 . Below we give a general solution of Eq. 2 . Generality is not lost when 6 I sin0 c COS0 c sin 02 and C4 COS02 and use the orthogonal condition c c C C4 0 which becomes sinO sinO cosOj cosO cos 0 - 0 0 4 and gives 0 -0 Tt 2 so that we obtain sinO2 - COS0 andcosO sin0 .Thus a general solution of sp hybridization is given by denoting 0 simply by 0 in the relations sin6 2 cos0 2pv ISP1 cos 6 2x sin 0 2px where the sign is taken so that Isp2 is elongated in the opposite direction to Ispị . This general sp solution is a two-dimensional unitary transformation which belongs to the special orthogonal group SO 2 of 12s and 2pr . The angle 0 and the signs in Eq. 5 are determined for each molecular orbital so as to minimize the total energy of the molecule. The elongation and the asymmetric shape of the sp hybridized orbital become maxima for 0 rt 4 which corresponds to Eq. 3 . When the two nearest neighbor atoms are different elements the coefficients are shifted from 0 rt 4. When an asymmetric shape of the charge density see Fig. 2 is needed to form a chemical bond then a mixing of 2p orbitals with 2s orbitals occurs. The mixing of 2p orbitals only with each other gives rise to the rotation of 2p orbitals because the 2px 2p _ and 2p. orbitals behave as a vector x y . The wave function Cx 12px Cv I 2ạ. c. 2p. where c2 Cy C2Z 1 is the 2p wave function whose direction of .