Pentagons in theSi(331)−(12×1)surface reconstruction
نویسندگان
چکیده
منابع مشابه
Fullerenes with distant pentagons
For each d > 0, we find all the smallest fullerenes for which the least distance between two pentagons is d. We also show that for each d there is an hd such that fullerenes with pentagons at least distance d apart and any number of hexagons greater than or equal to hd exist. We also determine the number of fullerenes where the minimum distance between any two pentagons is at least d, for 1 ≤ d...
متن کاملAcute Triangulations of Pentagons
An acute triangulation is a triangulation whose triangles have all their angles less than π 2 . In this paper we prove that i) every planar pentagon can be triangulated into at most 54 acute triangles, and ii) every double pentagon can be triangulated into at most 76 acute triangles.
متن کاملEmpty pentagons in point sets with collinearities
An empty pentagon in a point set P in the plane is a set of five points in P in strictly convex position with no other point of P in their convex hull. We prove that every finite set of at least 328` points in the plane contains an empty pentagon or ` collinear points. This is optimal up to a constant factor since the (` − 1) × (` − 1) grid contains no empty pentagon and no ` collinear points. ...
متن کاملSpherical Tiling by Congruent Pentagons
We consider tilings of the sphere by congruent pentagons. The basic example is dodecahedron, which has 12 pentagonal tiles. To simplify the problem, we assume the tiling is edge-to-edge and all vertices have degree ≥ 3.
متن کاملThe Grunert Point of Pentagons
1. Introduction. "Remarkable points" of triangles –– for example, the centroid, the circumcenter and others –– have been studied in detail; in fact, the recent book [3] by Clark Kimberling contains information on 400 such "centers". Although one can expect that in case of quadrangles there should be an even larger number of "remarkable points" –– only few have been discussed in the literature. ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Physical Review B
سال: 2017
ISSN: 2469-9950,2469-9969
DOI: 10.1103/physrevb.95.041412