Pantone PMS 7545 has no official Pantone name and is known by variations on grey and blue. Case University uses PMS 7545C as the official Case gray. Unofficial names include slate blue, graphite blue, and grey.
PMS 7545 is a theoretical colour and PMS 7545C is a specification for representing the colour on coated paper using specific Pantone inks. PMS 7545M is the specification for representing PMS 7545 on matte paper and PMS 7545U is the specification for uncoated paper. Uncoated paper is washed out, colours appear lighter, and PMS 7545U is probably a good starting point for presenting PMS 7545 on cheap low contrast LCD screens. PMS 7545C should be the starting point for good LCD screens and CRT screens. Matte paper diffuses light more than uncoated paper, making PMS 7545M unsuitable for comparison to any screen.
As an example of how hard colour representation can be, one online chart shows PMS 7545 as a green.
#51626f is a suggestion from Pantone for representing Pantone PMS 7545 in HTML.
#51626f is a suggestion from another site for representing Pantone PMS 7545 in HTML. Note that they suggest a different CMYK value.
HSV: 206° 27, 44
RGB: 81, 98, 111
XYZ 10.6, 11.6, 16.7
HSL 206°, 16, 38
CIE-L*ab 40.6, -3.2, -9.5
#5d6f7b is another suggestion for representing Pantone PMS 7545 in HTML.
CIE-L*ab: 45.6, -5, -6.1
CMYK: 21, 6, 0, 54
HSL: 197°, 12, 41
HSV: 197° 21, 46
RGB: 93, 111, 118
XYZ: 13.5, 15, 19.3
#616365,Pantone Cool Gray 10, is the closest named PMS colour.
HSV: 210° 4, 40
RGB: 97, 99, 101
XYZ 11.7, 12.4, 14.1
HSL 210°, 2, 39
CIE-L*ab 41.9, -0.4, -1.4
#666666 is a safe grey with a similar degree of darkness as #51626f on devices with limited colour. #666666 is close to the British Standard colour BS4800 10 A 11 Charcoal Grey.
Make up your own mind about the best screen colour to represent the colour you use for printed material, uniforms, signs, vehicles, and everywhere else. Test the HTML colour on a lot of screens including all the different Internet connected telephones.