Báo cáo "Nghiên cứu lý thuyết tương tác giữa C2H6, CH3CH2F, CH3CHF2, CH2FCHF2 và CHF2 với H2O " docx

T\lp chi Hoa h9C, T. 45 (2), Tr. 162 - 168, 2007 NGHIEN CO'U u THUYET TVONG TAc GIUA C 2H 6 , CH 3CH 2F, CH 3CHF 2 , CH 2FCHF 2 vA CHF 2CHF 2 VOl H 20 Den Toa sO(ln 12-5-2006 NGUYEN TIEN TRUNG'. TR~N THANH HUE', NGUYEN MINH THQ', NGUYEN TEl MINH HU$' I Khoa Hoa hoc, Dai hoc Quy nhon 'Khoa Hoa floc, Truong Dai hoc s« phamHa uo: 'Klwa Hoa hoc, Dai ho« Leuven, Vu<mg Qu& Bi "Truong Cao ddng su pham lla Tinh SUMMARY The binding energies of some the complexes (corrected by ZPE and BSSlo'j range between IJ.49 kcal.mol' and 2.62 kcal.mol:', There is a contraction of the Cf-I bond bound to urygen atom, a blue shift. There is a decrease of the occupation of the o*(Cl112) and 0*(C1H3) antibonding orbitals in the [fA, I/1B, IV respective complexes performed in the [irgure 1. The N 80 analysis indicates that the H-index is not a reason for physical nature of improper blue-shifting hydrogen bond in the complexes examined, but the EDT and the increase of s-charucter of CII bonding are major reasons for the contraction. The data obtained in this work allow us to establish the following correlations between the frequency shifts of the stretching vibrations and variations of the corresponding bond lengths: Lh(C-Il) = -12956 !Jr(C-Il) +2.01i6 (1). !J110-If) = -13349 !Jr(0-1l) + 1IJ.725. We also have deduced the correlation: !Jr(O-Ifj = 2.5075do*(O-1I) -IJ.0026. I - GI6I THI~U Lien ket hidro dong vai tro quan trong trong nhicu linh vue nhu hoa hoc, vat Ii va sinh hoc. S\I hinh thanh lien ket hidro X-H Y lam cho lien ket hoa tri X-II yeu di voi tan so dao dong hoa tri wang ung giam va cuong do hong ngoai tang la kieu lien ket hidro co dicn hay chuycn doi do, da duoc nghicn cuu kha day du. Tuy nhien, bang chirng thuc nghiern dau ticn ve do ben han ella lien ket X-H (X: C) (lien ket hidro chuyen doi xanh) da diroc tim thay khi do pho hong ngoai cua mot so floroparafin chua nhom - CHI', voi cac phan til nhan proton khac [Trudeau va cong su 1980]. Nhirng nghien ciru Ii thuyet gan day da chi ra fang lien ket hidro chuyen doi xanh khong chi 162 gioi han trong nnung hop chat co lien ket C-H rna con xuat hien trang cac lien ket SiH, PII, NIl, [1, 2. 5. 8, I I], cling da co nhieu bang chirng ve thuc nghiem cong nhan ykien nay. Tuy nhien, co sa lf thuyet cho ki~u lien ket hidro nay chua diroc nghien cuu mot each co he thong. Trong bai bao nay, chung tci khao sat pmrc cua elan va cac dan xuar Iloroetan voi mroc nharn tim xern co su chuyen doi xanh tan so dao dong hoa tri ella cac lien ket C-B hay khong, dong thoi gop phan tim hieu ban chat ella su khac nhau giira hai loai lien ket hidro chuyen doi xanh va do. II - PHUONG PIlAp TiNH Hmh h9C ella cac monome va phirc duoc toi . class="bi x0 y0 w2 h1 6" alt =""