Maximum coverage problem

My name is Jestine (34 years old) and my hobbies are Origami and Microscopy.

Here is my web site; http://Www.hostgator1centcoupon.info/ (support.file1.com)

Ligand K-edge XAS is a spectroscopic technique that allows the direct study of metal-ligand bonding. In a XAS experiment, electrons in ligand 1s orbitals are excited to unfilled p (principal quantum number n <= 4) and continuum states. This results in a large spectral feature known as a rising edge. Transitions at energies lower than the edge can occur, provided they are to orbitals with some ligand p character, and are called pre-edges. Such transitions are often observed in the data of complexes with metal-ligand bonding.

Pre-edge intensities (D₀) are related to the amount of ligand (L) character in the unfilled orbital:

$D_{0}(L\ 1s\rightarrow \psi ^{*})=const\ \vert \langle L\ 1s\vert \mathbf {r} \vert \psi ^{*}\rangle \vert ^{2}=\alpha ^{2}\ const\ \vert \langle L\ 1s\vert \mathbf {r} \vert L\ np\rangle \vert ^{2}$

where $\psi ^{*}$ is the wavefunction of the unfilled orbital, r is the transition dipole operator, and $\alpha ^{2}$ is the "covalency" or ligand character in the orbital. Since $\psi ^{*}={\sqrt {1-\alpha ^{2}}}\vert M_{d}\rangle -\alpha \vert L_{np}\rangle$, the above expression relating intensity and quantum transition operators can be simplified to use experimental values:

$D_{0}={\frac {\alpha ^{2}h}{3n}}I_{s}$

where n is the number of absorbing ligand atoms, h is the number of holes, and I_s is the transition dipole integral which can be determined experimentally. Therefore, by measuring the intensity of pre-edges, it is possible to experimentally the determine the amount of ligand character in a molecular orbital.