Forbidden transitions in benzene

Induced Nonradiative Transitions in Benzene

A nonradiative electronic transition in benzene occurs at about 2400 c m 1 above the zero-point vibration of the *B2u electronic state. The rate-determining step may be the vibrational relaxation of the product or the nonradiative transition itself. The rate of the latter is limited to 10s <C k\c < 1011 s e c 1 in the vapor at 100 torr and kxc ~ 1012 s e c 1 in liquids. There are also limiting ...

Forbidden transitions in a magneto-optical trap.

We report the first observation of a nondipole transition in an ultracold atomic vapor. We excite the 3P-4P electric quadrupole (E2) transition in 23Na confined in a magneto-optical trap, and we demonstrate its application to high-resolution spectroscopy by making the first measurement of the hyperfine structure of the 4P(1/2) level and extracting the magnetic dipole constant A=30.6+/-0.1 MHz. ...

On paths in grids with forbidden transitions

Finding Paths in Grids with Forbidden Transitions

A transition in a graph is a pair of adjacent edges. Given a graph G = (V,E), a set of forbidden transitions F ⊆ E × E and two vertices s, t ∈ V , we study the problem of finding a path from s to t which uses none of the forbidden transitions of F . This means that it is forbidden for the path to consecutively use two edges forming a pair in F . The study of this problem is motivated by routing...

Finding paths in graphs avoiding forbidden transitions

Let v be a vertex of a graph G; a transition graph T (v) of v is a graph whose vertices are the edges incident with v. We consider graphs G with prescribed transition systems T = { T (v) | v ∈ V (G) }. A path P in G is called T -compatible, if each pair uv, vw of consecutive edges of P form an edge in T (v). Let A be a given class of graphs (closed under isomorphism). We study the computational...