The highly stable nitrosyl iron(II) mononuclear complex [Fe(bztpen)(NO)](PF6)(2) (bztpen=N-benzyl-N,N',N'-tris(2-pyridylmethyl)ethylenediamine) displays an S=1/2 S=3/2 spin crossover (SCO) behavior (T-1/2=370 K, Delta H= 12.48 kJmol(-1), Delta S=33 JK(-1) mol(-1)) stemming from strong magnetic coupling between the NO radical (S=1/2) and thermally interconverted (S=0 S=2) ferrous spin states. The crystal structure of this robust complex has been investigated in the temperature range 120-420 K affording a detailed picture of how the electronic distribution of the t(2g)-e(g) orbitals modulates the structure of the {FeNO}(7) bond, providing valuable magneto-structural and spectroscopic correlations and DFT analysis. ; Spanish Ministerio de Economia y Competitividad (MINECO) ; FEDER funds CTQ2013-46275-P ; FEDER funds CTQ2015-64579-C3-1-P ; FEDER funds (Unidad de Excelencia Maria de Maeztu) MDM-2015-0538 ; Generalitat Valenciana PROMETEO/2012/049 ; Generalitat Valenciana ; Universidad de Valencia ; Generalitat de Catalunya ; Piñeiro López, L.; Ortega Villar, N.; Muñoz Roca, MDC.; Molnar, G.; Cirera, J.; Moreno Esparza, R.; Ugalde Saldivar, VM. (2016). Electronic Structure Modulation in an Exceptionally Stable Non-Heme Nitrosyl Iron(II) Spin-Crossover Complex. Chemistry - A European Journal. 22(36):12741-12751. doi:10.1002/chem.201601172. ; Senia ; 12741 ; 12751 ; 22 ; 36