Manu: added refs about state-driven correlations

Manuscript/eDFT.bib

@@ -3596,6 +3596,17 @@
 	Bdsk-Url-1 = {http://www.sciencedirect.com/science/article/pii/0009261479802766},
 	Bdsk-Url-2 = {http://dx.doi.org/10.1016/0009-2614(79)80276-6}}
 
+@article{Gould_2019_insights,
+author = "Tim Gould and Stefano Pittalis",
+title = "{Density Driven Correlations in Ensemble Density Functional Theory: Insights from Simple Excitations in    Atoms}",
+year = "2019",
+month = "10",
+url = "https://chemrxiv.org/articles/                                                                               Density_Driven_Correlations_in_Ensemble_Density_Functional_Theory_Insights_from_Simple_Excitations_in_Atoms/        9947249",
+doi = "10.26434/chemrxiv.9947249.v1"
+}
+
+
+
 @article{Gould_2019,
 	Author = {Gould, Tim and Pittalis, Stefano},
 	Date-Added = {2018-10-24 22:38:52 +0200},
@@ -6621,6 +6632,21 @@
 	Year = {2018},
 	Bdsk-Url-1 = {https://doi.org/10.1103/PhysRevA.98.022513}}
 
+@article{Senjean_2020,
+author = {Senjean, Bruno and Fromager, Emmanuel},
+title = {N-centered ensemble density-functional theory for open systems},
+journal = {Int. J. Quantum Chem.},
+volume = {n/a},
+number = {n/a},
+pages = {e26190},
+keywords = {embedding, ensemble density-functional theory, fractional electron number, grand canonical energy, open systems},
+doi = {10.1002/qua.26190},
+url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/qua.26190},
+eprint = {https://onlinelibrary.wiley.com/doi/pdf/10.1002/qua.26190},
+abstract = {Abstract Two (so-called left and right) variants of N-centered ensemble density-functional theory (DFT) are presented. Unlike the original formulation of the theory, these variants allow for the description of systems with a fractional electron number. While conventional DFT for open systems uses only the true electron density as basic variable, left/right N-centered ensemble DFT relies instead on (a) a fictitious ensemble density that integrates to a central (integral) number N of electrons, and (b) a grand canonical ensemble weight α which is equal to the deviation of the true electron number from N. Within such a formalism, the infamous derivative discontinuity that appears when crossing an integral number of electrons is described exactly through the dependence in α of the left and right N-centered ensemble Hartree-exchange-correlation density functionals. Incorporating N-centered ensembles into existing density-functional embedding theories is expected to pave the way toward the in-principle-exact description of an open fragment by means of a pure-state N-electron many-body wavefunction. Work is currently in progress in this direction.}
+}
+
+
 @article{Serrano-Andres_1993,
 	Author = {Serrano-Andr\'es, Luis and Merch\'an, Manuela and Nebot-Gil, Ignacio and Lindh, Roland and Roos, Bj\"orn O.},
 	Date-Added = {2018-10-24 22:38:52 +0200},