QM(DPT) and MD studies on formation mechanisms of C60 fullerenes

被引:42
作者
Hua, X [1 ]
Çagin, T [1 ]
Che, J [1 ]
Goddard, WA [1 ]
机构
[1] CALTECH, Div Chem & Chem Engn, Beckman Inst 139 74, Mat & Proc Simulat Ctr, Pasadena, CA 91125 USA
关键词
D O I
10.1088/0957-4484/11/2/308
中图分类号
TB3 [工程材料学];
学科分类号
0805 ; 080502 ;
摘要
One of the most puzzling aspects of fullerenes is how such complicated symmetric molecules are formed from a gas of atomic carbons, namely, the atomistic or chemical mechanisms. Are the atoms added one by one or as molecules (C-2, C-3)? Is there a critical nucleus beyond which formation proceeds at gas kinetic rates? What determines the balance between forming buckyballs, buckytubes, graphite and soot? The answer to these questions is extremely important in manipulating the systems to achieve particular products. A difficulty in current experiments is that the products can only be detected on time scales of microseconds long after many of the important formation steps have been completed. Consequently, it is necessary to use simulations, quantum mechanics and molecular dynamics, to determine these initial states. Experiments serve to provide the boundary conditions that severely limit the possibilities. Using quantum mechanical methods (density functional theory (DFT)) we derived a force field (MSXX FF) to describe one-dimensional (rings) and two-dimensional (fullerene) carbon molecules. Combining DFT with the MSXX FF,we calculated the energetics for the ring fusion spiral zipper (RFSZ) mechanism for formation of C-60 fullerenes. Our results shows that the RFSZ mechanism is consistent with the quantum mechanics (with a slight modification for some of the intermediates).
引用
收藏
页码:85 / 88
页数:4
相关论文
共 11 条
[1]   RELATIVE STABILITIES OF FULLERENE, CUMULENE, AND POLYACETYLENE STRUCTURES FOR CN - N = 18-60 [J].
FEYEREISEN, M ;
GUTOWSKI, M ;
SIMONS, J ;
ALMLOF, J .
JOURNAL OF CHEMICAL PHYSICS, 1992, 96 (04) :2926-2932
[2]  
GUO Y, 1992, THESIS CALTECH
[3]   ANNEALING CARBON CLUSTER IONS - A MECHANISM FOR FULLERENE SYNTHESIS [J].
HUNTER, JM ;
FYE, JL ;
ROSKAMP, EJ ;
JARROLD, MF .
JOURNAL OF PHYSICAL CHEMISTRY, 1994, 98 (07) :1810-1818
[4]   ANNEALING AND DISSOCIATION OF CARBON RINGS [J].
HUNTER, JM ;
FYE, JL ;
JARROLD, MF .
JOURNAL OF CHEMICAL PHYSICS, 1993, 99 (03) :1785-1795
[5]   STRUCTURES AND VIBRATIONAL FREQUENCIES OF THE CARBON MOLECULES C2-C18 CALCULATED BY DENSITY-FUNCTIONAL THEORY [J].
HUTTER, J ;
LUTHI, HP ;
DIEDERICH, F .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1994, 116 (02) :750-756
[6]   THE PERFORMANCE OF A FAMILY OF DENSITY FUNCTIONAL METHODS [J].
JOHNSON, BG ;
GILL, PMW ;
POPLE, JA .
JOURNAL OF CHEMICAL PHYSICS, 1993, 98 (07) :5612-5626
[7]   WHY POLYACETYLENE DIMERIZES - RESULTS OF ABINITIO COMPUTATIONS [J].
KONIG, G ;
STOLLHOFF, G .
PHYSICAL REVIEW LETTERS, 1990, 65 (10) :1239-1242
[8]   ISOMERS OF C-20 - DRAMATIC EFFECT OF GRADIENT CORRECTIONS IN DENSITY-FUNCTIONAL THEORY [J].
RAGHAVACHARI, K ;
STROUT, DL ;
ODOM, GK ;
SCUSERIA, GE ;
POPLE, JA ;
JOHNSON, BG ;
GILL, PMW .
CHEMICAL PHYSICS LETTERS, 1993, 214 (3-4) :357-361
[9]  
RIGNALDA MN, 1995, PS GVB V2 2
[10]   CARBON CLUSTER CATIONS WITH UP TO 84 ATOMS - STRUCTURES, FORMATION MECHANISM, AND REACTIVITY [J].
VON HELDEN, G ;
HSU, MT ;
GOTTS, N ;
BOWERS, MT .
JOURNAL OF PHYSICAL CHEMISTRY, 1993, 97 (31) :8182-8192