英语翻译Comparison of the stacking periodicity along the columnaraxis and that along the molecular disc normal (h0 and h,respectively) indicates that the molecules are stacked almostperpendicular to the columnar axis (see Table S1 in theSupportin

英语翻译Comparison of the stacking periodicity along the columnaraxis and that along the molecular disc normal (h0 and h,respectively) indicates that the molecules are stacked almostperpendicular to the columnar axis (see Table S1 in theSupportin
英语翻译
Comparison of the stacking periodicity along the columnar
axis and that along the molecular disc normal (h0 and h,
respectively) indicates that the molecules are stacked almost
perpendicular to the columnar axis (see Table S1 in the
Supporting Information).[16] Furthermore,the molecules
likely stack in an alternated fashion in order to fill the
available space between neighbors.This is also indicated by
molecular dynamics (MD) simulations in which a column
model was built from a periodic cylindrical cell with a 13.3-G
height (4 I 3.33 G,corresponding to four stacked molecules),
in keeping with the experimental X-ray data.These calculations
show a good space-filling of the available volume as
well as the enhancement of the microsegregation over the
entire simulation experiment time,contributing to the
cohesion of the columnar structure.Moreover,the model
showed that the cohesion of the columns is further reinforced
by Pt–Pt and Pt–alkyne interactions,as also revealed by the
sharp wide-angle signal (h0).The BF4
\3 anions are located
between the complexes.Snapshots of the MD experiment
account for the excellent molecular packing of 2c in the
hexagonal columnar (Colh) phase as shown in Figure 4.The
size of the central rigid electron-rich core is around 2 nm,a
value that is very close to the smallest width of a fiber as
determined for 2b by TEM in dilute gels.
Finally,the organization of these fibrillar superstructures
on well-defined crystallographic surfaces such as mica and
highly ordered pyrolytic graphite (HOPG) was also investigated
(note that the molecules were deposited on amorphous
carbon films for the TEM investigations).A diluted gel
(0.08 mmolL\31) of 2b was deposited by drop-casting on a
mica substrate.As shown in Figure 5a,fibers with no
apparent orientational order and an average height of 2 nm
(see cross-section of Figure 5b) are clearly visible.
Interestingly,a diluted dodecane gel of compound 2b
deposited by spin-coating on freshly cleaved HOPG leads to
self-assembly of molecular fibers that follow mainly the
preferential crystallographic directions of the underlying
HOPG substrate (Figure 5c).The threefold symmetry of
the segment pattern is particularly visible at intercepts where
the fibers form angles of 608 and 1208 to each other.The crosssections
show the presence of two types of fibers corresponding
to two different molecular heights,namely (2.0\50.1) nm
and (4.0\50.3) nm (Figure 5d).The 2-nm high fibers can be
considered to be made of single molecular layers that lie flat
on the surface (Figure S1 in the Supporting Information).The
4-nm high fibers are made of two such piled up layers,with
their alkyl chains still lying parallel to the surface.

英语翻译Comparison of the stacking periodicity along the columnaraxis and that along the molecular disc normal (h0 and h,respectively) indicates that the molecules are stacked almostperpendicular to the columnar axis (see Table S1 in theSupportin
沿着柱体轴线的堆积周期性和沿着分子盘法线（molecular disc normal）的堆积周期性(分别为h0和h)表明,分子几乎垂直于柱体轴线而堆积（参见支持信息中的表S1）[16].而且,为了填满邻近分子之间可得的空间,分子很可能以交替的形式堆积.这也被分子动力学（MD）仿真所表明,在此仿真中,遵照实验的X射线数据,由一个高度为13.3-Å(4×3.33 Å相当于4个堆积分子）的周期性的圆柱细胞建立了一个柱体模型.这些计算表明,可得的体积有良好的空间填充,以及在整个仿真实验时间内微偏析的增强,从而对柱状结构的内聚性做出了贡献.而且,该模型表明,柱体的内聚由于Pt－Pt和Pt－炔烃的互作用而进一步得到增强,就如也被尖锐的宽角度信号（h0）所揭示的那样.BF4－阴离子位于络合物之间.MD实验的快照解释了2c在六边形柱体（Colh）相中优异的分子包装,如图4所示的那样.
中心的刚性富电子核心的大小大约为2nm,这是一个非常接近于如2b在稀释凝胶下用TEM确定的一根纤维的最小宽度的值.
最后还研究了在定义良好的结晶学表面（例如云母和高度有序的热解石墨（HOPG）上的这些纤丝状超结构的组织（注意,分子沉积在无定形碳薄膜上用于TEM研究）.2b的稀释凝胶（0.08m mol L－1）用滴铸（drop casting）法沉积在云母基体上.如图5a中所示的那样,没有表观取向次序和平均高度为2nm的纤维清晰可见（参见图5b的横截面）
令人感兴趣的是,用旋转涂覆沉积在新鲜劈开的HOPG上的化合物2b的稀释的十二烷凝胶导致了分子纤维的自组合,它主要遵循着下面HOPG基体的优先结晶学方向（图5c）.片段图形三倍的对称性在纤维相互形成60°和120°角度的截距处特别可以看出.这些横截面表明了存在两种纤维,它们相应于两种不同的分子高度,即（2.0±0.1）nm和（4.0±0.3nm）（图5d）.此2nm高的纤维可以认为是由平坦处于表面上的单一的分子层构成的（支持信息中的图S1）.4nm高的纤维由两层这样堆积起来的层构成,它们的烷烃链仍与表面处于平行.