File Name : figure s1_final.tif Caption : singular values from the diagonal matrix s as determined by svd of the data matrix d. all singular values, s_i,i (i=1,..,n), obtained for every studied protein, are presented in figure by plotting singular values, s_i,i, in log scale versus component number, i. as it is seen, first two components stand out above the others, which, in their turn, form almost a straight line. the rank of matrix d is estimated as two by identification of two singular value components above the systematic decline. File Name : figure s2_final.tif Caption : singular value decomposition of the time-resolved spectra d(λ,t) measured after o₂ photodissociation from the isolated β^sh chains. description of each panel and symbols used is the same as for fig. 4. File Name : figure s3_final.tif Caption : correlation between time constants of temporal changes in the ν(fe-his) frequency following the co photodissociation and the means of the lifetime distribution peaks extracted from the second amplitude vector, v2. the time constants of temporal evolution of the ν(fe-his) band were taken from literature^13-17 and are listed in table s2 together with the corresponding data characterizing the lifetime distributions extracted from the second amplitude vector, v2. solid line represents fit to linear function of y = αx with the result of α = 0.97 ± 0.06. File Name : figure s4_final.tif Caption : populations of the unliganded (reagent) states (left column) and the unliganded subunits in the r* and r tertiary conformations (right column) predicted by the basic kinetic model for the isolated α^sh chains (panel (a) and (d)), for the α subunits within α₂(fe²⁺-o₂)β₂(fe³⁺-cn) valency hybrids (panel (b) and (e)), and for the β subunits within α₂(fe³⁺-cn)β₂(fe²⁺-o₂) valency hybrids (panel (c) and (f)). the populations obtained within the basic kinetic model are shown by lines. corresponding populations predicted by the extended kinetic model are shown by dotted lines of respective colors for comparison.