This sort of enquiey (from many students) is natural and innocent. It is easy to refer the student to some articles about interband/intraband scattering rates. The right job is how to transform this enquiry into another question, whose answer is clear and may be well known to him? 

In principle yes. There is no reason why they cannot; an electron is repelled by other electrons. The Cooper pairs behave in a different manner. This issue of electron-electron interaction is generally not important in deciding important collision parameters such as mean free time. The main collision objects for electrons and holes are the ionised dopants (Coulombic), phonons, and surface roughness (important in MOSFETs).

Great...Thank you for your valuable information.

Thank you for understanding the reason behind posting this question. I've at least succeeded to hear from great scientists, like you.

I still wait for more in depth & SIMPLE answers. SIMPLICITY

Scattering of Carrier-Carrier and Carrier-Phonon affects the photonic line shape function in the confinement of Quantum Wells

These papers I found during my MSc

 http://journals.aps.org/prb/abstract/10.1103/PhysRevB.36.8082 Theory of the carrier-carrier and carrier-phonon interactions under double injection into undoped quantum wells and its application to a laser problem; Masumi Takeshima

 http://dx.doi.org/10.1109/3.35228 Intraband relaxation time in quantum-well lasers; M. Asada ; Dept. of Phys. Electron., Tokyo Inst. of Technol., Japan

Martin Stutzmann, since you mentioned lattice temperature can you elaborate on the role of ambient temperature and lattice temperature on the carrier-carrier scattering which is purely Coulombic Interaction as you said? If you prefer not to answer I will understand given your 69.xx for RG score.

Samares Kar, could you refer to an introduction for how Cooper pair are different than two electrons scattering with Coulomb repulsion? Do you have another introduction for surface roughness and phonons scattering which are not charge repulsion in nature? What do you have to say about electron-hole scattering?

Thank you SifedDin, for raising these related questions.

I'm compiling and summarizing the answers, until I find the best (simple) answer. In my compilation, I add some personal notes that agree or disagree with the answer. Some of these notes show the confusion (and sometimes contradiction) between authors.

Interesting and somewhat Tricky discussion... Just to better understand the original question: are you talking of VALENCE electrons collisions, or perhaps you refer to unbound free (conduction) electrons collisions? All I read so far seems to apply to electrons free to move across the solid at a given T. However, I may be wrong and have not well understood the question.

Electrons  behave like waves also and electronic waves can be superimpose as wel as scatter in the  system but it can not effect on over chemistry of solid or system , if of solid temperature increases ,it increases over all energy of solid which can increase frequency and decrease wavelength of electronic waves,in the other hand valance electrons (waves)can collide with the cores of atoms in the solid (metal or semiconductor) collisions of electrons is completely elastic ,but if electronic waves are dragging by electromotive force in a particular dimension then collisions results power dissipation.

Regard 

Muhammad imran khattak 

Dear Giuseppe Curro ·

Thank you for your question. The question is about electron scattering in the valence band (s) of a solid which are more or less bound. The student was wandering how come all these orbitaling (valence) electrons move in harmony and don't collide in their wave motions (at least with themselves).

Muhammad Imran Khattak 

It's nice to see a Chemist's point of view. I see you mixed correlation of electrons with scattering, electron temperature with phonon frequency and electron energy with phonon energy. There is no electron frequency or wavelength for the wave function, but there is a phonon frequency. Yes the electron-phonon collisions are elastic for the two particles but an electron drifted by an electric field dissipates the power of that field through electron-phonon collisions as well.

Nice answer my friend, but I think I want to see a physicist's point of view, no offence to quantum chemist though.

Giuseppe Curro

I am really glad that you identify the essence of the question and the reason for me behind posting:

Everyone talks in the Semiconductor Material Books and Papers about hole-hole scattering in valence band, or electron electron scattering in conduction band, or even electron-hole pair recombination rates but no one is asking about electron-electron scattering in the valence band. I will not look naive and extend the question to hole-hole scattering in conduction band cause I will leave this to those who hail Fermi-Dirac distribution to be the origin of all electron-to-hole duality.

I hope you give us your answer from your expertise, Giuseppe or maybe ask one of your coworkers to join the quest.

Thank you Mahmoud for your acknowledgement.